Integrated cartridge for extracting a beverage from a particulate substance

0001The present invention relates to an integrated cartridge for extracting a beverage from a particulate substance, such as ground coffee, instant coffee, tea, powdered chocolate or milk, and the like.

0002It is known that machines for extracting a beverage from a particulate substance usually require that the particulate substance is placed into a filtering receptacle installed in the machine. In particular, automatic/semiautomatic espresso coffee machines comprise a filtering receptacle, also called filter holder, in which a dose of ground coffee is placed before the extraction of coffee beverage takes place.

0003The general steps for extracting a coffee beverage in an espresso coffee machine, which are substantially equivalent to those of other automatic machines for preparing a beverage starting from a powdered substance, comprise a phase of delivering hot water under suitable pressure into an extraction chamber which includes the filtering receptacle, a brewing phase and a phase of conveying the brewed beverage into an external cup or glass, ready to drink.

0004Ground coffee, as well as other particulate substances for preparing brewed beverages, is usually a single use substance, in that the organoleptic qualities such as taste, aroma and body of the brewed beverage are irremediably lost once ground coffee has been soaked. Accordingly, in espresso coffee machines and in other brewing machines the particulate substance has to be removed after one single brewing. This is the reason why the filtering receptacle housing a dose of ground coffee is usually manually removable from the espresso coffee machine, in order to allow emptying of the receptacle from the used ground coffee and filling it with a new dose of ground coffee.

0005In order to facilitate the operations of filling and emptying the filtering receptacle, single serving pre-packaged tablets of ground coffee have been provided, consisting of a dose of ground coffee contained in a filtering paper bag or sachet, to be placed directly in a filter holder of the espresso coffee machine. While this arrangement has resulted handy, it is affected by some drawbacks. In particular, the tablet is not air-tight and accordingly a second air-tight packaging must be provided for enclosing each dose, in order to keep the tablet uncontaminated from the external environment during storage.

0006Moreover, the user's hands come into contact with the tablet when the tablet is placed on the filter holder so that hygiene requirements are not fully assured.

0007In the past years, disposable capsules containing ground coffee have been also provided. Such capsules, generally having a frustum shape, are made of plastics or aluminum and provide a better air-tight barrier to the external environment than the filtering paper used in tablets.

0008A known capsule has a top surface that is pierceable by an injection needle/nozzle of the espresso coffee machine, in order to inject water under pressure inside the capsule, and a bottom surface comprising weakened zones which tear under pressure of percolation fluids. An internal filter is also provided inside the capsule for preventing solid substances from being ejected from the capsule together with the coffee beverage.

0009Another known capsule comprises a cylindrical body made of polypropylene, with a top and a bottom surface having a plurality of openings for distributing hot water throughout the dose of ground coffee, and comprising a sheet of paper filter for blocking passage of ground coffee outside the openings of the bottom surface during the extraction phase. These capsules have usually to be placed into a further packaging, such as a multilayered plastic sachet.

0010In order to prepare a coffee beverage, the known capsules and cartridges are placed into the filter holder, that constitutes an extraction chamber for coffee when it is installed on the coffee machine. During the extraction phase, the percolation fluids may come into contact with internal surfaces of the extraction chamber before definitively flowing out into the external coffee cup. Such contact contaminates the extraction chamber as well as the filter holder and after a number of coffee extraction operations the quality of the beverage is greatly reduced, suffering from residuals and contaminants in the extraction chamber.

0011Accordingly, the extraction assembly, comprising the extraction chamber and the filter holder, has to be accurately cleaned after a certain number of coffee extraction operations; in addition, decalcification must be performed on a regular basis.

0012Even when such cleaning operations are regularly carried out, the fluid turbulence inside the extraction chamber of the machine or the insufficient fluid-tight seal at the opened top surface of the capsule during water injection causes either the extracted beverage or the injected water to lap portions of the external surface of the capsule itself, thus jeopardizing the extraction hygiene requirements.

0013Another drawback of known capsules is that they do not retain percolation fluid residuals inside the capsule, in that perforations or openings on the top surface and/or on the bottom surface of the capsules provide for an escape for fluid residuals when the extraction is terminated and/or when the capsule is removed from the machine, causing the capsule to drip and dirt the surroundings of the coffee machine.

0014In addition, the known capsules and espresso coffee machines do not suffer from a limited hygienic character only, but they are often affected by a not so efficient distribution of hot water into the ground coffee and/or delivery of the coffee beverage.

0015In fact, in known capsules having a frustum shape, the hot water is injected into the internal volume by means of a nozzle that pierces the top surface, which has a smaller diameter than the bottom surface, so that hot water is sprayed from a single point rather than being evenly showered onto the whole dose of coffee. Accordingly, the hot water washes the coffee particles in an inhomogeneous way.

0016This drawback has been partially solved by the cartridge disclosed in <patcit id="pcit0001" dnum="EP1344722A"><text>EP-A-1344722</text></patcit>, wherein two discs are provided inside the cartridge having a plurality of openings and a plurality of embossings, in order to create a plurality of fluid channels. Unfortunately, such known cartridge has to be pierced on both the upper and the lower surface in order to extract the beverage, and the internal volume of the cartridge has to be burdened with additional elements such as distribution discs.

0017Yet another drawback of prior art cartridges is that they are not very handy, in that a user must control the insertion direction when he installs the cartridge into an extraction machine. This control may be facilitated by means of a particular shape of the cartridge's receptacle in the machine, but when the user is particularly hurried (for instance, when the user is a barman assigned to continuously and quickly prepare coffee beverages for many customers) even a control of a minor nature is unacceptable.

0018Aim of the present invention is to overcome the drawbacks of prior art cartridges and capsules by providing a cartridge and an extraction assembly for producing a high quality beverage having improved organoleptic qualities, particularly when the beverage extraction machine is an espresso coffee machine.

0019Within the scope of this aim, an object of the present invention is to greatly reduce or eliminate contamination of any component of machines for producing a beverage from a particulate substance, and to provide a universal beverage extraction system, which takes advantage of its contamination-free structure for allowing consecutive extractions of beverages from different kinds of particulate substances.

0020A second particular object of the present invention is to transfer most of the tasks that are conventionally performed by beverage extraction machines to the cartridges to be used in such extraction machines.

0021Another object of the present invention is to guarantee a high level of preservation of the particulate substance inside the cartridge until the cartridge is installed into the beverage extraction machine, reducing contamination of the particulate deriving from the external environment.

0022Another object is to simplify use of the cartridge, reducing the number of operations to be carried out for preparing the cartridge to installation into a beverage extraction machine.

0023A further object is to provide an improved even distribution of the injection fluid throughout the entire dose of particulate substance of the cartridge.

0024Yet another object is to simplify and reduce the internal load of the cartridge and the beverage extraction machine without affecting the quality of the final beverage.

0025Not least object of the invention is to provide a cartridge and an extraction assembly which speed up the beverage preparation operations.

0026This aim, these objects and other which will become apparent hereinafter are achieved by a cartridge according to claim 1.

0027Further characteristics and advantages of the invention will become better apparent from the following description of preferred but not exclusive embodiments, illustrated by way of non-limitative embodiments in the accompanying drawings, wherein: <ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">Figure 1</figref> is a perspective view of a cartridge which does not form part of the invention;</li><li><figref idref="f0002">Figure 2</figref> is a perspective, cross-sectional, exploded view of the cartridge of <figref idref="f0001">Figure 1</figref>, taken along plane A-A of <figref idref="f0001">Figure 1</figref>;</li><li><figref idref="f0003">Figure 3</figref> is a top view of the cup portion of the cartridge of <figref idref="f0001">Figure 1</figref>;</li><li><figref idref="f0003">Figure 4</figref> is a cross-sectional view of the cup portion of <figref idref="f0003">Figure 3</figref>, taken along plane B-B;</li><li><figref idref="f0004">Figure 5</figref> is a perspective cross-sectional view of a cartridge according to an embodiment of the invention;</li><li><figref idref="f0005">Figure 6</figref> is a perspective cross-sectional view of a cartridge according to an embodiment of the invention;</li><li><figref idref="f0006">Figure 7</figref> is a perspective broken away view of the shim of <figref idref="f0004">Figure 5</figref>;</li><li><figref idref="f0006">Figure 8</figref> is a perspective view of a cartridge according to an embodiment of the invention;</li><li><figref idref="f0007">Figure 9</figref> is a perspective cross-sectional exploded view of the cartridge of <figref idref="f0006">Figure 8</figref>;</li><li><figref idref="f0008">Figure 10</figref> is a perspective cross-sectional view of a cartridge according to the invention ;</li><li><figref idref="f0008">Figure 11</figref> is a perspective view of the inner side of the lid portion of the cartridge of <figref idref="f0008">Figure 10</figref>;</li><li><figref idref="f0009">Figure 12</figref> is a perspective view of an extraction assembly according to a second aspect of the invention;</li><li><figref idref="f0010">Figure 13</figref> is an exploded view of the extraction assembly of <figref idref="f0009">Figure 12</figref>;</li><li><figref idref="f0011">Figure 14</figref> is a perspective broken away view of the extraction assembly of <figref idref="f0009">Figure 12</figref> arranged in the beverage extraction position, having a cartridge installed therein;</li><li><figref idref="f0012">Figure 15</figref> is a perspective broken away view of an extraction assembly arranged in the beverage extraction position, having a discoidal cartridge installed therein;</li><li><figref idref="f0013">Figure 16</figref> is a perspective broken away view of the extraction assembly of <figref idref="f0009">Figure 12</figref> arranged in the cartridge expulsion position;</li><li><figref idref="f0014">Figure 17</figref> is a bottom view of the nozzle used in the extraction assembly of <figref idref="f0009">Figure 12</figref>;</li><li><figref idref="f0014">Figure 18</figref> is a partial cross-sectional lateral view of the nozzle used in the extraction assembly of <figref idref="f0009">figure 12</figref>;</li><li><figref idref="f0015">Figure 19</figref> is a cross-sectional lateral view of the nozzle used in the extraction assembly of <figref idref="f0012">Figure 15</figref> ;</li><li><figref idref="f0016">Figure 20</figref> is a perspective cross-sectional view, taken along a radial plane, of the cartridge according to a further embodiment of the invention;</li><li><figref idref="f0017">Figure 21</figref> is a broken away view of an extraction assembly according to a further embodiment of the invention, in which the cartridge of <figref idref="f0016">Figure 20</figref> is installed.</li></ul>

0028With reference to <figref idref="f0001">Figures 1</figref> and <figref idref="f0002">2</figref>, a cartridge <b>1</b> is shown which does not form part of the present invention but which comprises some of the features of the invention. The cartridge has a generally cylindrical shape and comprises a cup portion <b>2</b> and a lid portion <b>3</b> fixed thereon.

0029In particular, the cup portion <b>2</b> comprises a substantially circular base <b>7,</b> a cylindrical sidewall <b>8</b> extending from base <b>7</b> and a rim <b>9a,</b> which is disposed substantially opposite to the base <b>7</b> and defines an open end of the cup portion <b>2.</b>

0030An internal volume is defined by the cup base <b>7,</b> the sidewall <b>8</b> and the lid portion <b>3,</b> when the lid portion is fixed on the cup portion. A dose of ground coffee <b>4</b> is housed in such internal volume and it is sandwiched between filtering means, preferably consisting of a first paper filter <b>5b</b> and a second paper filter <b>5a.</b> In an alternative embodiment, a tablet of a known kind can be provided, as it will be described hereafter.

0031The cup portion <b>2</b> comprises a cup port <b>6a,</b> which is preferably located in a central region of the cup base <b>7</b> and protrudes outwardly with respect to the internal volume of the cartridge, forming a spout. As shown in <figref idref="f0002">Figure 2</figref>, the cup port <b>6a</b> has a substantially cylindrical shape and provides for open access to the internal volume of the cartridge, thus allowing passage of fluids to or from the internal volume of the cartridge. To this aim, the opening <b>103a</b> is provided on the cup base <b>7</b> in correspondence of the cup port <b>6a,</b> as it is shown in <figref idref="f0003">Figure 4</figref>.

0032The cup base <b>7</b> optionally comprises a flange <b>105a,</b> aligned with sidewall <b>8</b> and protruding outwardly with respect to the internal volume of the cartridge. Such flange is preferably provided in order to end up with a protruding shape facilitating and promoting handling and automated production processes. Furthermore the capsule can be placed in a horizontal position on a table surface without tilting or rolling, it can be packaged and stacked more easily and it can also be "strip" packaged, i.e. fixed and sealed between two strips of polylaminate films..

0033The lid portion <b>3</b> is shaped so as to fit with the open end of the cup portion <b>2</b> and comprises a lid base <b>7b,</b> from which a substantially cylindrical sidewall <b>105b</b> extends upwardly and slightly outwardly and which is substantially perpendicular to the lid base <b>7b.</b> The sidewall <b>105b</b> ends with an annular edge <b>9b</b> that is located substantially opposite to the lid base <b>7b</b> and that protrudes outwardly from the sidewall <b>105b,</b> in order to fit with and lean on the rim <b>9a</b> of the cup portion <b>2.</b> Preferably, the annular edge <b>9b</b> has a substantially stepped cross section, so as to engage with a complementary support located at the rim <b>9a</b> of the cup portion <b>2,</b> as depicted in <figref idref="f0003">Figure 3</figref>. Other cross-sectional shapes of the annular edge <b>9b</b> and of the rim <b>9a</b> can be alternatively provided, as long as these shapes allow to fix the lid portion on the cup portion.

0034In preferred embodiments, the lid portion and the cup portion are welded to each other using an ultrasonic shear-welding technique. Alternatively, other known welding techniques can be used, for instance common ultrasonic welding, hot welding, bonding and so on. The cartridge according to the invention may also be manufactured as a single moulded piece.

0035The protruding sidewall <b>105b</b> is preferably provided in order to facilitating and promoting handling and automated production processes, as well as to dissociate the shear welding region away from the coffee tablet, thus minimizing interferences of migrating coffee particles with the plastic weld, which might compromise its tight sealing characteristics.

0036In the preferred embodiment depicted in <figref idref="f0001">Figures 1</figref> and <figref idref="f0002">2</figref>, the lid portion <b>3</b> comprises a lid port <b>6b</b> in a central region of its base <b>7b,</b> having a generally cylindrical shape and protruding from base <b>7b</b> outwardly with respect to the internal volume of the cartridge. The lid port <b>6b</b> provides for open access to the internal volume of the cartridge, thus allowing passage of fluids to or from the internal volume. To this aim, the opening <b>103b</b> is provided on the lid base <b>7b</b> in correspondence of the lid port <b>6b,</b> as shown in <figref idref="f0002">Figure 2</figref>.

0037In alternative embodiments, described hereafter, the lid port does not protrude from the lid base <b>7b</b> or is normally closed, being pierceable by an injection needle or nozzle during the extraction phase. Alternative embodiments of a similar kind will be presented hereafter.

0038In the cartridges according to the invention, either the lid port <b>6b</b> or the cup port <b>6a</b> may comprise hurdles for deviating a fluid flow. In particular, referring back to the embodiment of <figref idref="f0002 f0003">Figures 2-4</figref>, a first barrier <b>104a</b> is provided on the internal side of the cup base <b>7</b> so that it radially crosses the central opening <b>103a</b> from which the spout <b>6a</b> protrudes, and second barriers <b>106a, 107a</b> are provided on the internal surface of the cup port 6a at a distance from the first barrier and from the opening <b>103a.</b>

0039Preferably, second barriers <b>106a</b> and <b>107a</b> face each other and protrude from the internal surface of the cup port <b>6a</b> so as to define a sort of zigzag path for the fluid passing through the cup port <b>6a,</b> thus breaking any direct fluid flow to or from the internal volume of the cartridge and avoiding exceedingly accelerated fluid flow, which may cause jet-spray effects such as spattering.

0040The first barrier <b>104a</b> is particularly useful for either deviating the fluid flow or providing a support against filter paper deformation that may result from the hydraulic extraction fluid pressure. Accordingly, obstruction of the openings <b>103a</b> and possible breaking of the filter paper are prevented.

0041Additionally or alternatively, corresponding fluid flow barriers <b>104b</b> and <b>107b</b> are also provided at lid port <b>6b,</b> as seen in <figref idref="f0002">Figure 2</figref>. In particular, the barrier <b>104b</b> spans the lid opening <b>103b,</b> while the barrier <b>107b</b> protrudes from the internal surface of the lid port <b>6b,</b> facing an identical barrier in order to define a fluid flow pathway substantially analogous to that formed inside the cup port <b>6a.</b>

0042Notwithstanding preferred embodiments of the cartridge according to the invention comprise fluid flow hurdles as depicted in <figref idref="f0002 f0003">Figures 2-4</figref>, the skilled in the art easily appreciates that alternative arrangements or shapes of fluid flow hurdles can be used for the same purpose. For instance, a cross-shaped fluid flow barrier may be provided, so as to support the paper filter and break direct fluid flow into four separate flows. Alternatively, radial projections formed around the lid or the cup opening and radially protruding towards the center of such opening may be provided, as it will be described hereinafter with reference to <figref idref="f0016">Figure 20</figref>.

0043Fluid flow hurdles may not be directly formed on the internal surface of the cartridge, but they may be a separate means which can be inserted and fixedly attached to an inlet or an outlet port of the cartridge. For instance, a small plastic tube with both open ends closed by a fluid permeable filter material (for instance, films of thermoplastic sieve material or open mazed tissue or paper). An example of a separate fluid flow hurdle will be described hereinafter with reference to <figref idref="f0016">Figure 20</figref>.

0044Moreover, the fluid flow hurdles may be provided at both the lid and cup ports, at only one of such ports, or may not be provided at all, according to fluid flow requirements.

0045The cup portion <b>6a</b> further comprises a plurality of ridges <b>101a</b> directly formed on the base <b>7</b> and protruding towards the internal volume of the cartridge, in particular towards the external surface of the paper filter 5a. The ridges <b>101a</b> directly contact paper filter <b>5a</b> so as to form a plurality of small channels <b>102a, 102b,</b> which put in a fluid communication the whole bottom surface of the filter-coffee assembly <b>4, 5a</b> with the cup port <b>6a.</b> Such channels, preferably, have an average width/height of about 1mm.

0046Similarly, ridges <b>101b</b> are provided on the lid portion <b>3</b> which protrude towards the internal volume of the cartridge, in particular towards the upper surface of the paper filter <b>5b.</b> A plurality of small channels is accordingly provided between the filter <b>5b</b> and the lid base <b>7b,</b> connecting the lid port <b>6b</b> to the whole top surface of the filter-coffee assembly <b>4, 5b.</b>

0047In alternative embodiments, small fluid channels may be provided on cup portion only, or on lid portion only, or they may not be provided at all. In such cases, a reduced number of ridges is preferably formed on either the cup base or the lid base, and they protrude towards the internal volume of the cartridge in order to form an air space between the cup/lid base and the filtering means. An exemplary arrangement of such kind will be explained hereafter with reference to <figref idref="f0008">Figure 11</figref>.

0048Alternatively, in order to provide a fine canalization on at least a portion of the internal surface of the cartridge facing one of the top surface or the bottom surface of the dose comprising the ground coffee and the filtering means, a disc of porous material may be arranged between such dose and cup port or the lid port. Preferably, such disc extends throughout the top or the bottom surface of the dose.

0049Even though not explicitly shown in <figref idref="f0001 f0002 f0003">Figures 1-4</figref>, the lid port and/or the cup port are preferably plugged by a film, for instance made of multilayered plastics, which can be manually removed or can be pierced or torn by the machine during the extraction phase.

0050Alternatively, the lid port or the cup port may be plugged by an integrated surface created during the manufacturing of the lid portion or by a rubber plug or seal, to be described thereafter, or the entire cartridge may be kept in a sachet or packaging to be manually opened before use. The sachet or packaging may be made of a polylaminate vacuumed or filled with an inert gas under pressure (such as in Modified Atmosphere Packaging or MAP techniques).

0051Either the lid port or the cup port may be alternatively sealed by means of edible solid substances (e.g. polysaccharides, proteins and lipids) that are air-impermeable and water-soluble or that melt at the temperature of the inlet water.

0052The cartridge <b>1</b> is preferably made of polypropylene and it is manufactured using known injection moulding techniques. Anyway, this cartridge as well as any cartridge according to the invention may be made of any material such as: other thermoplastic materials, for instance PET; elastomeric-thermoplastic materials or TPEs, for instance, SANTOPRENE, i.e. a mixture of non interlaced EPDM and polypropylene; thermosetting compositions, for instance, a polyester; rubbers or elastomers, for instance, silicone or MVQ; polylaminate thermoplastic materials, for instance a composite sheet made of PE, PET and PVDC; aluminium; other polylaminate materials, for instance, a composite sheet made of PE, PET and aluminium. The cartridge <b>1</b> may also be manufactured using other techniques, such as thermoforming.

0053The main body of an exemplary cartridge such as the one depicted in <figref idref="f0001">figure 1</figref> is, for instance, 30-35mm high and 35-40mm wide, and the lid port and the cup port are about 7-8mm high and 8-10mm wide. However, the skilled in the art readily understands that the size of the cartridges according to the invention may be different, according to the extraction requirements and the structure of the beverage extraction machine.

0054Having now defined the main characteristics of cartridge <b>1,</b> it can be appreciated that this cartridge eliminates the traditional contamination of the extraction chamber of a coffee machine, in that the cup port/spout <b>6a</b> acts as an outlet for directing the extracted beverage directly into an external cup that is then used for drinking. The spout <b>6a</b> is accordingly shaped so as to fit in known filter holders or so as to outwardly protrude with respect to purpose-built filter holders, thus keeping perfectly clean the internal surfaces of the filter holder and prevent the extracted beverage exiting the cartridge from contacting such surfaces.

0055Additionally, the small channels directly formed on the internal surface of the cup portion allow to eliminate additional fluid director members from the inside of the cartridge and advantageously combine with the cup port so as to define an integrated conveyor for the extracted beverage. At the same time, the small channels allow to keep the internal pressure level drop of the cartridge at a substantially lower value between upper zone and lower zone of the coffee cake, so that the full volume of ground coffee is exploited and the resulting beverage has enhanced organoleptic qualities.

0056For functional reasons, it is preferable to keep the space between the coffee cake and base of the cup portion or the lid portion as little as possible.

0057Another improvement involved by the particular cartridge of <figref idref="f0001">Figure 1</figref> is that it is reversible, i.e. it can be inserted also upside-down. In fact, the main body of the cartridge is shaped so as to be substantially symmetrical with respect to an virtual plane perpendicular to the water injection axis. In particular, the cup port <b>6a</b> ant the lid port <b>6b</b> are substantially identical in shape and size, they are aligned on a same water injection axis and the height of flange <b>105a</b> is substantially equal to the height of the cylindrical sidewall <b>105b,</b> as illustrated in <figref idref="f0002">Figure 2</figref>. Advantageously, a fine canalisation is provided on both the internal surfaces of the cup portion and of the lid portion.

0058Accordingly, the cartridge <b>1</b> can be installed in a filtering receptacle regardless of which port will act as the inlet port and which port will act as the outlet port, thus greatly facilitating the operation of inserting the cartridge into an extraction machine.

0059While characteristics have been shown with reference to the exemplary cartridge of <figref idref="f0001 f0002 f0003">Figures 1-4</figref>, embodiments of the invention can be provided by either suitably combining the fundamental characteristics already illustrated or by adding other features still falling within the scope of the invention.

0060With reference to <figref idref="f0004">Figure 5</figref>, a preferred embodiment of the invention is illustrated. In particular, <figref idref="f0004">Figure 5</figref> is a cross-sectional view of a cartridge <b>11</b> which, even though the main body is externally similar to that depicted in <figref idref="f0001">Figure 1</figref>, features internal variants.

0061While only a sectional view of cartridge <b>11</b> is shown in <figref idref="f0004">Figure 5</figref>, it is understood that this view is taken along a virtual radial plane halving the whole actual cartridge, which is not shown in the Figures for clarity reasons. It is clear that the skilled in the art has no difficulty in picturing the structure of the whole cartridge <b>11</b> starting from the sectional view of <figref idref="f0004">Figure 5</figref>.

0062The cartridge <b>11</b> has a generally cylindrical shape and comprises a cup portion <b>12</b> and a lid portion <b>13.</b> The cup portion <b>12</b> comprises a base <b>17,</b> a sidewall <b>18</b> and a rim <b>19a</b> that is disposed substantially opposite to the base <b>17</b> and defines an open end of the cup portion <b>12.</b>

0063An internal volume is defined by the cup base <b>17,</b> the sidewall <b>18</b> and the lid portion <b>13,</b> when the lid portion is mounted on the open end of the cup portion <b>12.</b> A dose of ground coffee is housed in such internal volume, enclosed by filtering means either in a way similar to that depicted in <figref idref="f0002">Figure 2</figref> or as in a tablet or cake of a known kind, as it will be better described hereafter.

0064In <figref idref="f0004">Figure 5</figref>, both the ground coffee and the filtering means have been omitted for simplicity, but it is intended that they substantially fill the internal volume of the cartridge, as it occurs in the embodiment of <figref idref="f0002">Figure 2</figref>.

0065The cup portion <b>12</b> comprises a cup port <b>16a,</b> preferably located in a central region of the cup base <b>17</b> and protruding outwardly with respect to the internal volume of the cartridge. The cup port <b>16a</b> has a substantially cylindrical shape and provides for open access to the internal volume of the cartridge, thus allowing passage of fluids to or from the internal volume of the cartridge. To this aim, an opening <b>113a</b> is provided on the cup base <b>17</b> in correspondence of the cup port <b>16a.</b>

0066The cup base <b>17</b> preferably comprises a flange <b>115a,</b> aligned with the sidewall <b>18</b> and protruding outwardly with respect to the internal volume of the cartridge.

0067The lid portion <b>13</b> is shaped so as to fit with the open end of the cup portion <b>12</b> and comprises a lid base <b>17b,</b> from which a substantially cylindrical sidewall <b>115b</b> extends upwardly and slightly outwardly. The sidewall <b>115b</b> ends with an annular edge <b>19b</b> that is located substantially opposite to lid base <b>17b</b> and that protrudes outwardly from the sidewall <b>115b,</b> in order to fit with and lean on rim <b>19a</b> of the cup portion <b>12.</b>

0068Preferably, the annular edge <b>19b</b> has a substantially stepped cross section, so as to engage with a complementary support located at the rim <b>19a</b> of the cup portion <b>12,</b> as depicted in <figref idref="f0004">Figure 5</figref>. Alternatively, other cross-sectional shapes of the annular edge <b>19b</b> and of the rim <b>19a</b> can be provided, as long as such shapes allow to fix the lid portion on the cup portion.

0069The lid portion <b>13</b> further comprises a normally closed lid port <b>16b,</b> preferably located in a central region of the base <b>17b</b> and protruding outwardly with respect to the internal volume of the cartridge <b>11.</b> The wording "normally closed" as intended herein indicates a port which is air-tight sealed before extraction and it is opened either manually by a user or automatically by the beverage extraction machine, for example by piercing the surface that plugs the port.

0070In the embodiment of <figref idref="f0004">Figure 5</figref>, the lid port <b>16b</b> is plugged by a weakened small surface <b>14</b> that is integrated with the lid port <b>16b.</b> Alternatively, the lid port may be plugged by a plastic film welded on the external mouth of the lid port or by a rubber or rubber-like plug or seal, described hereafter.

0071The internal surface of the lid port <b>16b</b> is substantially smooth, but fluid flow hurdles can be alternatively provided as those described with reference to the embodiment of <figref idref="f0002">Figure 2</figref>.

0072The cup portion <b>12</b> comprises a cup port <b>16a,</b> located on the cup base <b>17</b> and preferably having a substantially cylindrical shape. In the preferred embodiment depicted in <figref idref="f0004">Figure 5</figref>, the cup port <b>16a</b> is located in the central region of the base <b>17,</b> protrudes outwardly with respect to the internal volume of the cartridge <b>11</b> and comprises hurdles <b>114, 117a</b> and <b>117b</b> for breaking direct fluid flow passing through the cup port.

0073The first hurdle <b>114</b> is formed inside the cup port <b>16a</b> in the proximity of its output mouth so as to radially cross the internal volume of the cup port, while the second hurdles <b>117a</b> and <b>117b</b> flange out the internal surface of the cup port and face each other.

0074Similarly to the embodiment depicted in <figref idref="f0002">Figure 2</figref>, the cup portion <b>12</b> comprises a plurality of ridges <b>111a</b> that are directly formed on the internal side of the base <b>17</b> and protrude towards the internal volume of the cartridge. The ridges <b>111a</b> define a plurality of small channels <b>112a, 112b</b> between the cup base <b>17</b> and the filtering means, for conveying the extracted beverage to the cup port <b>16a.</b>

0075In the particular embodiment shown in <figref idref="f0004">Figure 5</figref>, unlike lid portion <b>3,</b> a fine canalisation is not provided between the lid portion and the assembly consisting of the ground coffee and the filtering means. Instead, sparse ridges <b>111b</b> are provided on the bottom side of the lid portion <b>13,</b> serving the purpose of creating a very small gap between the lid portion and the ground coffee. However, it is clear that as an alternative to this arrangement a canalisation may still be provided, as described above with reference to the lid portion <b>3.</b>

0076Advantageously, the cartridge <b>11</b> comprises valve means, for regulating the fluid flow passage through the cup port <b>16a.</b> The valve means are particularly conceived for application to the cup port, but they can be applied to both the cup port and the lid port of a cartridge according to the invention, or to the lid port only, according to the functional requirements of the cartridge.

0077In the embodiment shown in <figref idref="f0004">Figure 5</figref>, the valve means lean on an annular recess <b>15,</b> that is formed around the opening <b>113a</b> and cover opening <b>113a.</b> To this aim, the thickness of the base <b>17</b> preferably tapers from the cup port 16a towards the periphery, to allow the formation of the recess <b>15.</b>

0078The valve means preferably comprises a rubber (e.g. silicone rubber), rubber-like, elastomeric or plastic pad or disc having a narrow through slit or orifice formed therein connecting a top surface to a bottom surface of the pad. If no axial pressure is applied to the pad, the slit provides for an air-tight seal, whereas if an axial pressure is applied, such as the pressure of percolation fluids extracted from the ground coffee, a portion of the pad warps and the slit slightly widens, thus allowing passage of the percolation fluids, i.e. of the beverage.

0079According to the particular embodiment depicted in <figref idref="f0004">Figure 5</figref>, the valve means comprise a rubber pad or disc <b>116,</b> leaning on the recess <b>15</b> so as to air-tightly close the aperture <b>113a</b> of the cup port and acting as a septum. While the pad <b>116</b> is described as simply leaning on the recess <b>15,</b> it may optionally be bonded to such recess or otherwise fixed using known techniques.

0080The pad <b>116</b> comprises a top circular surface and a bottom circular surface and a slit <b>118</b> that axially traverses the pad from the centre of the top surface to the centre of the bottom surface.

0081The slit <b>118</b> is a pre-pierced one and it is preferably made using a thin needle. The slit may alternatively be a radial linear or cross-shaped cut or incision, or a plurality of slits may be provided through the pad, as long as these slits, cuts or incisions do not substantially allow passage of air inside the cartridge when the cartridge is not under fluid pressure and allow passage of percolation fluids during the beverage extraction phase.

0082In order to provide a support for the filtering means enclosing the ground coffee and to convey the extracted beverage to the pad <b>116,</b> a shim <b>119</b> is advantageously mounted on the cup base <b>17</b> and upstream of the pad <b>116.</b>

0083With particular reference to the broken away view of <figref idref="f0006">Figure 7</figref>, the shim <b>119</b> comprises a bottom surface that faces the pad <b>116</b> and that is shaped so as to define fluid flow channels <b>319</b> between the shim and the pad: to this aim, the bottom surface of the shim <b>119</b> comprises radially oriented ridges <b>219.</b>

0084The top surface of the shim <b>119</b> comprises ribs for supporting the coffee-filtering means assembly, which are preferably sized so that the thickness of the shim <b>119</b> is substantially equal to the height of the ridges <b>111a</b> of the cup portion <b>12.</b>

0085In alternative embodiments, not shown in the Figures, the shim may comprise through holes for conveying the percolation fluids to the rubber pad, or it may be substituted by any other supporting means that separate the dose of ground coffee from the rubber pad, such as those depicted in <figref idref="f0016">Figure <b>20</b></figref> to be described hereinafter.

0086Yet in another embodiment, the valve means do not comprise a separate shim at all. For instance, a further embodiment of the invention comprising such alternative valve means comprises only a pad or disc, made of rubber, rubber-like, elastomeric, or whichever resilient material.

0087In particular, with reference to <figref idref="f0005">Figure 6</figref>, a cartridge <b>21</b> according to a further preferred embodiment of the invention comprises a cylindrically shaped cup portion <b>22,</b> comprising a base <b>27,</b> a sidewall <b>28</b> and an open end on which a lid portion 23 is engaged so as to define an internal volume of the cartridge. Inside the cartridge, a dose of ground coffee and the corresponding filtering means are provided as in the previously described cartridges, but they are not shown in <figref idref="f0005">Figure 6</figref>, for simplicity.

0088The lid portion <b>23</b> comprises a normally closed lid port <b>26b</b> and it has substantially the same features of the already described lid portion <b>13.</b>

0089The cup portion <b>22</b> comprises a cup port <b>26a,</b> inside which fluid flow hurdles <b>124, 127a</b> and <b>127b</b> are provided. Moreover, the top surface of the base <b>27</b> comprises a plurality of ridges <b>121,</b> which ridges are distributed throughout the surface of the base <b>27</b> substantially as ridges <b>111a</b> and which converge to an annular recess <b>25.</b> A circular rubber pad <b>126</b> leans on the recess <b>25</b> so as to air-tightly plug the aperture <b>123a</b> of the cup port <b>26a.</b> Notwithstanding pad <b>126</b> is herein described as simply leaning on recess <b>25,</b> it may optionally be bonded to an edge of such recess or be otherwise fixed through known means.

0090Similarly to pad <b>116,</b> pad <b>126</b> comprises a through slit <b>128</b> at its centre, which slit is normally closed and slightly widens, thus allowing passage of the percolation fluids, during the beverage extraction phase.

0091In order to support the dose of ground coffee and the filtering means, the pad <b>126</b> preferably comprises ribs <b>129,</b> which are directly formed on its top surface and shaped so as to allow the passage of fluids directly deriving from the coffee/filter assembly and from the channels defined by ridges <b>121.</b>

0092Pads <b>116</b> and <b>126</b> have been described as being made of rubber, elastomeric or other flexible materials. The elastic properties of such materials allow a pre-pierced orifice or channel such as the slit <b>118</b> or the slit <b>128</b> to act as an air-tight seal, but at the same time allow to readily respond to pressure stresses directed either towards or from the internal volume of the cartridge. In other words, such pads act as valves or baffles.

0093Therefore, a cartridge comprising such pads requires no means for plugging the cup port - or the lid port, if the pad is applied to the lid port in a way similar to that described above -, such as films or pierceable diaphragms. At the same time, after the extraction phase has terminated, the sudden fall of internal pressure causes the slit to return in the initial rest condition, thus preventing possible internal fluid residuals to drip out of the cartridge.

0094Beyond its valve-like functioning that protects the cartridge from negative environment influences, at the same time permitting degassing of the cartridge and the extraction fluid to drop after extraction, the above described pad also allows the insertion of liquid inert gas from the outside by means of a hollow needle during the packaging phase (MAP), in order to condition the capsule and prepare it for longer storage periods. The rubber pad then closes automatically by its own elasticity after the needle has been pulled out. The same needle may be the one that pierces the pad so as to form the slit referred to above.

0095At the same time, another important advantage brought by pads according to the invention is the great improvement in the forming and stability of the appreciated cream layer on top of the extraction beverage, which is usually identified with the Italian term "crema" when referred to espresso coffee extraction methods.

0096The espresso extraction method results in a polyphasic beverage constituted by a foam layer of small bubbles with dispersed fine particles that create the typical and particular tiger-tail pattern on top of an emulsion of microscopic oil droplets in an aqueous multi-component solution with dispersed gas bubbles and solid particles.

0097The foam formation is related to surfactants naturally present in coffee and to a number of phenomena which are triggered by espresso extraction methods.

0098The supernatant foam of espresso coffee or crema is an extremely important organoleptic characteristic and represents a mark of distinction between espresso coffee and other preparations.

0099It is well known that the foam characteristics are the signature of a perfect preparation, being any error (for instance in coffee grinding, water temperature, water pressure, percolation time and/or beverage volume, etc) or any change (coffee blend, roasting, etc.) immediately denounced by the colour, the texture and the persistence of espresso foam.

0100As described above, the valve means according to the preferred embodiment of the invention comprise at least a rubber or rubber-like pad or disc having a through slit whose diameter is very small, e.g. in the order of 0,1 to 0,5 mm when it is opened. Forcing the extracted coffee through it has been found to greatly increase the density and the stability of the crema. This effect is a very advantageous one since, through the integration of a means of a relatively light weight and of simple nature, it is possible to achieve an important effect that characterizes the quality of an espresso coffee beverage.

0101Moreover, since the rubber pad for crema formation is integrated with the cartridge, which is generally a disposable one, it is guaranteed that the extracted espresso coffee has a layer of crema of the best quality, contrary to the known espresso coffee machines in which the devices that enhance the formation of crema are part of the machines, they are used for a great number of extraction processes and may deteriorate the quality of the extracted coffee over time.

0102Cartridges according to the invention are not to be limited to the substantially cylindrical cartridges described here above. Particularly, the term "cylinder" has to be read in a broad general meaning and indicates the surface traced by any line moving parallel to a fixed axis and intercepting a closed line. For instance, the main body of the cartridge according to particular embodiments of the invention can be either parallelepiped-shaped or discoid-shaped, too. Furthermore, the term "substantially cylindrical" also indicates cylindrical cartridges having a slight frustum shape, that is to say, for instance, the slope of the sidewall of a cartridge according to the invention can deviate for 1-2 degrees from a perfect cylindrical surface.

0103A parallelepiped-shaped cartridge, not shown in the Figures, is particularly a preferred one when small space occupancy is required.

0104A discoid-shaped cartridge, instead, can be advantageously provided in the alternative for other reasons, which will be now explained. An exemplary embodiment of the invention in which the main body of the cartridge is substantially discoid-shaped is depicted in <figref idref="f0006">Figures 8</figref> and <figref idref="f0007">9</figref>. A cartridge <b>31</b> of this kind embodies some of the features of the above cartridges, in particular it comprises a cup portion <b>32</b> and a lid portion <b>33,</b> both of them having substantially the shape of a dish.

0105The cup portion <b>32</b> comprises a base <b>37,</b> an annular sidewall and a flanged rim <b>39a</b> that is directed substantially parallel to the base <b>37</b> and, similarly, the lid portion <b>33</b> comprises a base, a sidewall and a flanged rim <b>39b</b> that is shaped so as to engage with the rim <b>39a,</b> thus defining an internal volume of the cartridge. The internal volume of the cartridge is shaped so as to fully house a ground coffee tablet or cake <b>34</b> of a known kind, such as the tablet called E.S.E.^®.

0106Such known tablet comprises a dose of ground coffee encapsulated within a filter paper sachet, whose peripheral edge is tightly retained by rims <b>39a</b> and <b>39b</b> when the cartridge <b>31</b> is in the assembled condition. Rims <b>39a</b> and <b>39b</b> may be reciprocally fixed using any known method such as ultrasonic welding, hot element welding, or other welding techniques, gluing or combinations of these with common border forging or deforming methods.

0107The cup portion <b>32</b> further comprises a substantially cylindrical cup port <b>36a</b> protruding outwardly with respect to the internal volume of the cartridge <b>31,</b> which is advantageously provided with inside hurdles <b>137a</b> and <b>134a</b> for breaking direct fluid flows passing through the cup port, which are similar to the above described hurdles <b>117a, 117b, 114.</b>

0108The base <b>37</b> comprises a plurality of ridges <b>131</b> distributed on its planar inner side, which define a plurality of small channels between the tablet <b>34</b> and the base <b>37.</b> The ridges <b>131</b> surround a central annular recess <b>35,</b> similar to the above described recesses <b>15</b> and <b>25,</b> on which a rubber pad <b>136</b> leans.

0109The pad <b>136</b> has a through, normally closed slit at its centre and supporting ribs on its top surface for supporting the tablet <b>34</b> and allowing fluid passage there-between. It is seen that the pad <b>136</b> is similar to the above described pad <b>126.</b>

0110A lid port <b>36b</b> protrudes from the central region of the lid portion <b>33</b> and comprises reciprocally facing hurdles <b>137b</b> on its internal surface.

0111<figref idref="f0007">Figure 9</figref> is a cross-sectional view of cartridge <b>31</b> and, as such, shows only one hurdle <b>137b,</b> but it is understood that an identical hurdle is present on the opposite side of the internal surface of the lid port that faces the depicted one. Moreover, the opening from which the lid port <b>36b</b> protrudes out is bridged by a fluid flow barrier <b>134b,</b> that is substantially analogous to the above described barrier <b>104b.</b>

0112The lid port <b>36b</b> is plugged by a film of aluminium or polylaminate plastics <b>38,</b> that forms an air-tight seal for the lid port before installing the cartridge into an espresso coffee machine. The film <b>38</b> is preferably pierceable by the injection needle of the machine, but a manually removable film may be provided in the alternative.

0113As in the cartridges depicted in <figref idref="f0004">Figures 5</figref> and <figref idref="f0005">6</figref>, the lid portion <b>33</b> comprises sparse ridges on the surface directed towards the internal volume, which define a very small gap between the coffee tablet <b>34</b> and the lid portion itself.

0114The cartridge <b>31</b> is particularly advantageous in that it is fully compatible with existing coffee tablets. The manufacturing process of this cartridge is also sped up, since no further filtering means have to be inserted into the cartridge.

0115Moreover, it is seen that the cartridge <b>31,</b> as well as the other cartridges described above, is an all-in-one cartridge, that is to say a cartridge in which most of functional features of standard espresso coffee machine, such as filtering, water distribution, crema enhancement and beverage delivery are integrated into the cartridge itself. The espresso coffee machine functions are mainly to support the cartridge and to inject water under pressure inside it.

0116<figref idref="f0008">Figure 10</figref> is a cross-sectional view of a cartridge <b>41</b> according to yet another embodiment of the present invention. This cartridge comprises most of the features of cartridge <b>1,</b> that is to say a cylindrical cup portion <b>42</b> whose base <b>47</b> comprises a plurality of ridges <b>141a</b> and a spout <b>46a</b> with fluid flow hurdles <b>144</b> and <b>147,</b> a dose of ground coffee <b>4</b> and filter paper sheets <b>5a</b> and <b>5b.</b> An aluminium or multilayered plastics film <b>45</b> plugs the external mouth of the spout 46a and it is manually removable.

0117Differently from the embodiment of cartridge <b>1,</b> the lid portion <b>43</b> having a substantially flat shape is provided, comprising a lid port <b>46b</b> which only slightly protrudes from the plane of the lid portion and an annular edge <b>49b</b> that slightly protrudes from the contour of the lid portion.

0118With reference to <figref idref="f0008">Figures 10 and 11</figref>, the inner side of the lid portion <b>43</b> comprises sparse radial ridges <b>141b</b> that slightly protrude towards the internal volume of the cartridge, so as to create a small gap between the upper filtering means <b>5b</b> and the lid portion <b>43.</b>

0119Moreover, the lid portion <b>43</b> comprises a rubber/rubber-like plug or seal <b>48</b> that engages the mouth defined by the lid port <b>46b.</b> The plug <b>48</b> is preferably made of a thermoplastic elastomer (TPE) such as EPR or SBS and has a central thinner portion that is pierceable, for instance by an injection needle or a nozzle of the espresso coffee machine, and has a thicker portion surrounding such central portion that grips the mouth of the lid port <b>46b.</b>

0120The thicker and central portions of the plug <b>48</b> are sized so as to sealingly engage with the tube or nozzle that delivers water to the cartridge. In other words, the plug <b>48</b> acts as a radial fluid-tight seal for the injection tube or nozzle, thus preventing the injected water to splash out of the lid port <b>46b</b> during the beverage extraction phase.

0121As the extraction phase is terminated and the cartridge <b>41</b> is separated from the injection nozzle, the plug <b>48</b> elastically returns to a rest position due to its resilient nature and, even though it has been pierced, it is a good retainer for solid and fluid residuals, which are kept inside the cartridge as soon as it is removed from the machine.

0122While the plug <b>48</b> has been illustrated inside the cartridge <b>41,</b> it is understood that such plug can be applied to any other cartridge according to the invention, such as to the cartridges previously described.

0123<figref idref="f0016">Figure 20</figref> depicts a cartridge <b>81</b> according to a further embodiment of the invention. This cartridge comprises features substantially corresponding to those of cartridge <b>21,</b> that is to say a cylindrical cup portion <b>82a</b> whose base <b>87a</b> comprises a plurality of ridges <b>181</b> and channels <b>182</b> directly formed thereon and an externally protruding cup port <b>86a,</b> a lid portion <b>83a</b> being fixedly attached to the upper rim of the cup portion <b>82a</b> so as to define an internal volume in which a cake of ground coffee and filtering means (not shown) are housed.

0124The lid portion <b>83a</b> comprises a base <b>87b,</b> on which sparse ridges are formed similar to ridges <b>111b,</b> and comprises a normally closed lid port <b>86b,</b> which is preferably located in a central region of the base <b>87b</b> and protrudes outwardly with respect to the internal volume of the cartridge <b>81.</b> The lid port <b>86b</b> is plugged by an aluminium or polylaminated plastics film.

0125The internal surface of the lid port <b>86b</b> is substantially smooth and a cross-shaped fluid flow hurdle <b>89</b> quarters the opening <b>183b</b> from which the lid port <b>86b</b> protrudes. The hurdle <b>89</b> preferably protrudes towards the internal volume of the cartridge, so that the filtering means that covers the cake of particulate substance is kept at a distance away from the base <b>87b</b> of the lid portion <b>83a.</b>

0126The diameter of the lid port <b>86b</b> is generally wider than the ones of the other lid ports described above, in order to completely receive a water injection nozzle without the need of using a needle for accessing the internal volume of the cartridge. The internal diameter of the lid port is preferably at least 5mm wide, but such diameter may be even wider, e.g. it may be substantially equal to the diameter of the lid base <b>87b.</b>

0127The ridges <b>181</b> of base <b>87a</b> surround a central annular recess <b>85a</b> formed around the opening <b>183a</b> from which the cup port <b>86a</b> protrudes. The ridges that closely surround the opening <b>183a</b> comprise projections <b>184</b> that radially extend towards the center of the opening <b>183a</b> and that are as thick as the ridges <b>181</b> themselves. The projections <b>184</b> act both as a support for the cake of particulate substance and the filtering means and as a fluid flow hurdle for breaking direct fluid flow.

0128The cartridge <b>81</b> further comprises a rubber pad <b>186,</b> which is installed between the projections <b>184</b> and the annular recess <b>85a</b> and which comprises a central through slit. The rubber pad <b>186</b> is a valve means as intended above.

0129The cup port <b>86a</b> advantageously comprises a fluid flow hurdle <b>187,</b> which is a separate piece that is inserted into the cup port and is tightly engaged with the internal surface of the cup port. Providing a separate fluid flow hurdle and eliminating the hurdles directly formed on the internal surface of a port is an advantageous arrangement that is particularly suited for the so-called sequential moulding manufacturing techniques.

0130The "separate" hurdle <b>187</b> preferably comprises a small plastic hollow tube <b>188</b> whose open ends are closed with a fluid permissive filter material, for instance a film of plastic sieve material or open mazed tissue/paper. Alternatively, internal barriers can be formed on the internal surface of the tube <b>188,</b> which are substantially similar to barriers <b>114, 117a</b> and <b>117b</b> described above.

0131In the embodiment depicted in <figref idref="f0016">Figure 20</figref>, the tube <b>188</b> comprises an upper sieve film <b>185b</b> and a bottom sieve film <b>185a.</b> In order to fix the hurdle <b>187</b> to the inner surface of cup port <b>86a,</b> the tube <b>188</b> comprises an annular rib <b>189a</b> on its outer sidewall for snap-fitting with a corresponding annular recess <b>189b</b> formed around the inner surface of the cup port <b>86a.</b> Obviously, many other arrangements for fixing a separate hurdle means to the cup port or the lid port are clearly in the reach of the skilled in the art.

0132Various embodiments of the cartridge according to the invention have been described hereinabove. According to a second aspect of the invention, an extraction assembly for application to standard espresso coffee machine or to another machine which can pump hot water or other infusion fluids under pressure for producing beverages will be now described in detail.

0133With reference to <figref idref="f0009 f0010 f0011">Figures 12-14</figref> an extraction assembly <b>60</b> according to a preferred embodiment of the invention comprises a support connectable to an espresso coffee machine, which is preferably composed of a connector member <b>62,</b> for connecting the extraction assembly to the water injection tube of the beverage extraction machine, and a bayonet holder <b>63.</b>

0134The connector member <b>62</b> has a base and a cylindrical sidewall raising from the base and ending with a flanged rim that serves for mounting the support on the extraction machine (not shown), for instance by using screws. The base of the connector member <b>62</b> comprises a protruding inlet port 65 connectable to the water outlet of the extraction machine and, on the opposite side of the base, a circular guiding wall <b>259,</b> which is described hereinafter.

0135The bayonet holder <b>63</b> has a substantially cylindrical shape and comprises an upper open end into which the cylindrical sidewall of connector member <b>62</b> fits. Preferably, the bayonet holder <b>63</b> is fixed to the connector member <b>62</b> by means of the same screws used for mounting the connector member to the extraction machine. Obviously, the bayonet holder and the connector member may be reciprocally fixed in any other known way; for instance, the outer surface of the cylindrical sidewall of the connector member and the upper inner surface of the cylindrical sidewall of the bayonet holder may be threaded. Alternatively, the connector member and the bayonet holder may be built as a single piece.

0136The bayonet holder <b>63</b> further comprises a bottom open end on which guides <b>263</b> of a known kind are provided for bayonet fitting with a cartridge holder <b>64,</b> which is provided with a grip handle <b>61.</b>

0137The cartridge holder <b>64</b> comprises a substantially cylindrical body that is internally shaped so as to completely house the cartridge <b>21.</b> In particular, it comprises a cylindrical sidewall that is complementary to the sidewall <b>28</b> of the cartridge.

0138Moreover, the base of the cartridge holder <b>64</b> comprises an annular groove <b>261,</b> into which the flange <b>125a</b> of the cartridge fits slidingly, and a bottom <b>250,</b> which is located inside the cylindrical body of the cartridge holder and comprises an opening <b>267</b> at its central region.

0139The depth of the annular groove <b>261</b> is substantially equal to the height of the flange <b>125a,</b> so that when cartridge <b>21</b> is inserted into the cartridge holder <b>64,</b> the surface of the base <b>27</b> leans almost completely against the bottom <b>250</b> and the cup port <b>26a</b> protrudes from the opening <b>267.</b>

0140The extraction assembly <b>60</b> further comprises an injection nozzle assembly <b>265a, 265b</b> that is firmly mounted on the bottom open end of the inlet <b>65</b> facing the cartridge holder, for instance by a thread fitting. Alternatively, the nozzle assembly and the water inlet port <b>65</b> may be made in a single piece.

0141With reference to <figref idref="f0014">Figures 17 and 18</figref>, the nozzle assembly comprises a hollow nozzle body <b>265a</b> and a piercing member or needle <b>265b</b> fixedly mounted to the inner surface of the nozzle body. More in detail, the nozzle body is substantially tubular and comprises two open ends <b>251</b> and <b>254.</b>

0142The open end <b>254</b> is located at the bottom end of the nozzle body and it is wide enough to receive a projecting lid port of a cartridge according to the invention, for instance lid port <b>26b.</b>

0143The open end <b>251</b> is defined at the upper end of the nozzle body by the wall <b>253,</b> which is shaped so as to tightly fit with the inner surface of the bottom open end of the inlet <b>65.</b> The external surface of the upper wall <b>253</b> and the internal surface of the inlet <b>65</b> may be threaded so as to secure the nozzle body to the connector member <b>62.</b> Alternative arrangements for coupling the nozzle assembly to the inlet of the connector member may be also provided, as long as a fluid tight fit is guaranteed between them.

0144The external surface of the nozzle body <b>265a</b> comprises a radially protruding stepped portion <b>257</b> for limiting the axial displacement of a cartridge ejector <b>269,</b> as described below. The internal surface of nozzle body <b>265a,</b> instead, comprises an annular projection <b>252</b> that extends inwardly and which is preferably located in a middle region of the internal surface of the nozzle body.

0145The needle <b>265b</b> is axially inserted and secured in the opening defined by annular projection <b>252.</b> In order to allow passage of fluid from the upper open end <b>251</b> to the bottom open end <b>254,</b> through openings <b>256</b> are provided in the annular projection <b>252.</b>

0146The internal surface of the nozzle body <b>265a</b> further comprises an annular recess <b>255,</b> which is located in a bottom region of the same internal surface, preferably around the bottom open end <b>254.</b> Such recess houses an O-ring <b>266,</b> which acts as a means for providing a radial fluid-tight seal between the nozzle assembly and the inlet port <b>26b</b> of the cartridge <b>21</b> during the beverage extraction phase.

0147A great advantage brought about by the O-ring <b>266</b> is that it prevents the injected water from contaminating any internal component or surface of the extraction assembly <b>60</b> and from lapping the outer surface of the cartridge, which has to be touched and handled by the user. Accordingly, superior hygienic conditions are guaranteed and the extraction machine can be used hundreds of times without having to clean the components of the extraction assembly, such as the cartridge holder <b>64</b> and the support <b>62, 63.</b>

0148Such a contamination-free arrangement also advantageously combines with the integration of an outlet spout in the cartridge according to the invention. The same beverage extraction machine and the same extraction assembly can be consecutively used for cartridges containing different edible substances, such as coffee, chocolate, tea or herbal infusions, soups, other hot milk beverages, without incorporating the main disadvantage of common systems that contaminate and negatively influence the extraction results of consecutive beverage extractions.

0149Moreover, the resilient nature of the O-ring <b>266</b> allows to use various cartridges having inlet ports of different radial sizes, as long as these radial sized do not exceed the average diameter of the bottom opening <b>254</b> of the nozzle assembly.

0150In order to enhance the practicality of the extraction assembly, a cartridge ejector <b>269</b> is mounted in the annular space defined by the guiding wall <b>259</b> and the portion of the nozzle body <b>265a</b> protruding out of the water inlet <b>65.</b> The cartridge ejector <b>269</b> is substantially toroidal and is preferably shaped so as to fit into the annular space defined by the guiding wall <b>259,</b> the base of connector member <b>62,</b> the lid portion of the cartridge and the portion of nozzle body <b>265a</b> protruding out of the water inlet <b>65</b> during the extraction phase.

0151The cartridge ejector <b>269</b> comprises a plurality of springs <b>268</b> located in respective hollow housings having an open end from which the springs can extend. The springs <b>268</b> abut against the base of the connector member <b>62</b> and against respective abutment surfaces provided inside the hollow housings of the cartridge ejector.

0152When the cartridge holder <b>64</b> is fixed to the bayonet holder <b>63,</b> the ejector <b>269</b> is pushed towards the base of the connector member <b>62</b> and the springs <b>268</b> are compressed. As it is seen in <figref idref="f0011">Figure 14</figref> in this position the lid port <b>26b</b> is pierced by the needle <b>265b</b> and water can be injected inside the cartridge as described above.

0153As soon as the cartridge holder is removed, the ejector <b>269</b> keeps the cartridge <b>21</b> inside the cartridge holder <b>64,</b> as it is seen from <figref idref="f0016">Figure 20</figref>. In order to stop the ejector's travel when the cartridge holder is released, an annular projection <b>258</b> is provided around the internal surface of the toroidal body of the cartridge ejector, which abuts against the stepped portion <b>257</b> of the nozzle body <b>265a</b> when the ejector slides downwardly towards the cartridge holder.

0154While a particular embodiment of an extraction assembly for an espresso coffee machine has been described with reference to a cartridge of the kind shown in <figref idref="f0005">Figure 6</figref>, it is understood that any equivalent extraction assembly can be provided that is particularly suited for any cartridge according to the invention.

0155For instance, with reference to <figref idref="f0012">Figure 15</figref>, a particular extraction assembly <b>70</b> suited for a discoidal cartridge <b>71</b> according to the invention can be designed, according to the above teachings.

0156The discoidal cartridge <b>71</b> has not been described in detail so far, but it is immediately derivable by combining features of embodiments of the cartridge according to the invention which have already been described in detail. This combination is hereby presented to show that elements from different embodiments may be combined to obtain further embodiments that clearly fall under the same inventive concept and which are clearly in the reach of the skilled in the art.

0157The cartridge <b>71</b> incorporates features of cartridges <b>11, 31</b> and <b>41.</b> In detail, it has a general discoidal shape and houses a coffee tablet of a known kind, as cartridge <b>31.</b> The cup portion of cartridge <b>71</b> is similar to the cup portion <b>37,</b> but comprises a shim <b>119</b> and a rubber valve or pad <b>116</b> of the kind used in cartridge <b>11;</b> the pad <b>116</b> is depicted in a deformed condition, which is reached during the extraction phase. Differently form cartridge <b>31,</b> the lid port only slightly protrudes with respect to the lid portion and it is closed by a rubber plug or seal <b>78,</b> identical to the plug <b>48</b> used in cartridge <b>41.</b>

0158Accordingly, the extraction assembly <b>70</b> comprises a support connectable to an espresso coffee machine, which is preferably composed of a connector member <b>72,</b> for connecting the extraction assembly to the water injection tube of the beverage extraction machine, and a bayonet holder <b>73.</b>

0159The connector member <b>72</b> comprises a water inlet port <b>75,</b> for connection to a water injection port of a beverage extraction machine, and a annular wall <b>359</b> protruding towards the internal volume of the bbayonet holder <b>73</b> when this is mounted on the connector member.

0160The bayonet holder <b>73</b> has a substantially cylindrical shape and comprises an upper open end into which the annular wall <b>359</b> of the connector member <b>72</b> fits. Preferably, the bayonet holder <b>73</b> is fixed to the connector member <b>72</b> by means of the same screws used for mounting the connector member to the extraction machine. Obviously, the bayonet holder and the connector member may be reciprocally fixed in any other known way; for instance, the outer surface of the cylindrical sidewall of the connector member and the upper inner surface of the cylindrical sidewall of the bayonet holder may be threaded. Alternatively, the connector member and the bayonet holder may be built in a single piece.

0161The bayonet holder <b>73</b> further comprises a bottom open end on which guides <b>263</b> of a known kind are provided for bayonet fitting with a cartridge holder <b>74.</b>

0162The cartridge holder <b>74</b> comprises a substantially flattened body whose internal shape is complementary to the cup portion of cartridge <b>71.</b> Moreover, the base of the cartridge holder <b>74</b> comprises an opening <b>377</b> at its central region through which a cup port <b>76a</b> of cartridge <b>71</b> is arranged.

0163When the cartridge holder <b>74</b> is firmly secured to the bayonet holder <b>73,</b> the peripheral flat rim <b>79</b> of cartridge <b>71</b> is tightly kept between the annular wall <b>359</b> and the rim of cartridge holder <b>74.</b>

0164The extraction assembly further comprises a nozzle <b>275</b> that is secured to the inlet port <b>75</b> and that protrudes towards the cartridge holder.

0165Referring to <figref idref="f0015">Figure 19</figref>, the nozzle <b>275</b> is a substantially cylindrical hollow piece having an inner axial cavity <b>359</b> for receiving water from the water inlet <b>75</b> and having a needle or piercing member <b>358</b> integrated therein. The cavity <b>359</b> extends as far as the needle, which is axially hollow and comprises radial through openings <b>356</b> for supplying water in a substantially radial direction.

0166An annular recess <b>355</b> is further provided in the nozzle <b>275,</b> in particular around the needle <b>358.</b> The recess <b>355</b> is shaped so as to receive the thicker peripheral portion of the plug <b>78</b> as soon as the cartridge holder <b>74</b> is secured to the bayonet holder <b>73.</b> As it is noted from <figref idref="f0012">Figure 15</figref>, in this position the plug <b>78</b> is pierced by the needle <b>358,</b> so that water can be injected inside the cartridge, and the plug <b>78</b> provides for a fluid-tight seal between the nozzle <b>275</b> and the lid port of cartridge <b>71.</b> Therefore, the plug <b>78</b> acts as a means for providing radial fluid-tight seal between the water inlet port of the extraction assembly and the cartridge, thus preventing the injected water from lapping the external surface of the cartridge.

0167Advantageously, the extraction assembly <b>70</b> comprises a cartridge ejector <b>369</b> that is housed in the annular space defined by the wall <b>359</b> and the nozzle <b>275</b> and that is similar to the ejector <b>269.</b>

0168When the cartridge holder <b>74</b> is fixed to the bayonet holder <b>73,</b> the ejector <b>369</b> is pushed upwardly towards the connector member <b>72</b> by means of springs <b>368,</b> which are accordingly compressed. Instead, when the cartridge holder <b>74</b> is removed from the bayonet holder <b>73,</b> the ejector <b>269</b> keeps the cartridge <b>71</b> inside the cartridge holder <b>74.</b> In order to stop the ejector's travel when the cartridge holder is released, an annular projection <b>378</b> is provided around the internal surface of the toroidal body of the cartridge ejector <b>369,</b> which abuts against the stepped portion <b>357</b> of the nozzle body <b>275</b> when the ejector slides downwards towards the cartridge holder.

0169The above extraction assemblies comprise an injection nozzle that is provided with a needle for breaking the plug or seal of the upper port of the cartridge and for accessing the internal volume of the cartridge. Moreover, the upper ports of the above cartridges are sized so as to be insertable into a corresponding female nozzle. However, it is possible to provide an opposite coupling between the injection nozzle and the upper port of a cartridge without departing from the scope of the present invention. For instance, with reference to <figref idref="f0017">Figure 21</figref>, an extraction assembly according to another embodiment of the invention comprises a support connectable to an espresso coffee machine, which is preferably composed of a connector member <b>582,</b> for connecting the extraction assembly to the water injection tube of the beverage extraction machine, and a bayonet holder <b>583.</b>

0170The connector member <b>582</b> has a base and a cylindrical sidewall raising from the base and ending with a flanged rim that serves for mounting the support on the extraction machine (not shown), for instance by using screws. The base of the connector member <b>582</b> comprises a protruding inlet port <b>585</b> connectable to the water outlet of the extraction machine and, on the opposite side of the base, a circular guiding wall <b>559.</b>

0171The bayonet holder <b>583</b> has a substantially cylindrical shape and comprises an upper open end into, which the connector member <b>582</b> fits. Preferably, the bayonet holder <b>583</b> is fixed to the connector member <b>582</b> by means of the same screws used for mounting the connector member to the extraction machine, as in the embodiments described here above. Obviously, the bayonet holder and the connector member may be reciprocally fixed in any other known way; for instance, the outer surface of the cylindrical sidewall of the connector member and the upper inner surface of the cylindrical sidewall of the bayonet holder may be threaded. Alternatively, the connector member and the bayonet holder may be built as a single piece.

0172The bayonet holder <b>583</b> further comprises a bottom open end on which guides of a known kind are provided for bayonet fitting with a cartridge holder <b>584.</b>

0173The cartridge holder <b>584</b> comprises a substantially cylindrical body that is internally shaped so as to completely house the above described cartridge <b>81.</b> In particular, it comprises a cylindrical inner sidewall that is complementary to the sidewall of the cartridge.

0174Moreover, the base of the cartridge holder <b>584</b> comprises an annular groove <b>561</b> into which the lower flange of the cartridge <b>81</b> fits slidingly, and a bottom <b>550</b> that is located inside the cylindrical body of the cartridge holder and that comprises an opening <b>567</b> at its central region. The annular groove <b>561</b> and the bottom <b>550</b> are shaped so that when the cartridge <b>81</b> is inserted into the cartridge holder <b>584,</b> the surface of its base <b>87a</b> leans almost completely against the bottom <b>550</b> and the cup port <b>86a</b> protrudes from the opening <b>567.</b>

0175The extraction assembly of <figref idref="f0017">Figure 21</figref> further comprises an injection nozzle <b>575</b> that is firmly mounted on the bottom open end of the inlet <b>585</b> facing the cartridge holder, for instance by a thread fitting. Alternatively, the nozzle assembly and the water inlet port <b>585</b> may be made in a single piece.

0176The nozzle <b>575</b> comprises a hollow cylindrical body with opposite open ends and comprises a flange <b>557</b> in a middle region thereof.

0177A hollow tip end <b>558</b> of a substantially cylindrical shape protrudes axially from the flange <b>557</b> of the nozzle towards the cartridge holder and it is shaped so as to have an external diameter that is generally smaller than the inner diameter of the lid port <b>86b.</b> Accordingly, the tip end <b>558</b> can be completely inserted into the lid port when the cartridge holder <b>584</b> is fixedly mounted on the bayonet holder <b>583,</b> thanks to the appositely wide lid port 56b.

0178The tip end <b>558</b> is substantially wider than a (common) injection needle, but it is small enough to be insertable as a male part into a cartridge port such as the lid port <b>86b.</b> Advantageously, the tip end <b>558</b> comprises an annular recess formed around its external surface, for housing a sealing means such as an O-ring <b>566.</b>

0179Advantageously, the extraction assembly comprises a toroidal cartridge ejector <b>569,</b> which is housed in the annular space defined by the wall <b>559</b> of the connector member and the nozzle <b>575</b> and which is similar to the other cartridge ejectors described here above.

0180The axial travel of the ejector <b>569</b> is limited by means of common snap-brackets <b>578,</b> which extend upwardly and which are slidingly inserted into an appropriate annular recess <b>579</b> surrounding the nozzle <b>575.</b> The limit stop for the snap-brackets <b>578</b> is defined by the flange <b>557</b> of the nozzle <b>575.</b>

0181Advantageously, the toroidal cartridge ejector <b>569</b> comprises an inner concentric sidewall <b>568</b> that is sized so as to define an annular gap between the tip end <b>558</b> of the injection nozzle, which gap is completely filled with the sidewall of the lid port <b>86b</b> when the cartridge <b>81</b> is mounted into the extraction assembly. Therefore, in the particular arrangement depicted in <figref idref="f0017">Figure 21</figref>, the cartridge ejector acts also as a retaining wall against a possible expansion of the lid port during the extraction phase.

0182The extraction assembly of <figref idref="f0017">Figure 21</figref> benefits of a simple arrangement that eliminates piercing needles and, at the same time, guarantees a contamination-free coupling between the cartridge, the extraction chamber and the water injection chamber. In fact, regardless of whether the lid port is closed or not before installing it into the extraction assembly, the injection nozzle acts as a male part and the lid port as a female part, and the injection nozzle can pierce the upper seal, if any, of the lid port without the need of an appropriate needle.

0183The injection portion <b>575, 585</b> of the extraction assembly is kept insulated from the extraction chamber defined by the cartridge by means of an external O-ring, and a very high number of consecutive extraction processes of the same or different beverages can be carried out without cleaning or servicing in any way the extraction assembly.

0184Moreover, the external O-ring <b>566</b> of the injection nozzle can be easily replaced or serviced without having to access internal parts of the injection nozzle itself.

0185It has thus been shown that the present invention fulfils the proposed aim and objects. Clearly, several modifications to either the cartridges and the extraction assemblies according to the invention will be apparent to and can be readily made by the skilled in the art without departing from the scope of the present invention, as defined by the appended claims.

0186Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.