Patent Publication Number: US-2021169261-A1

Title: Method and apparatus for preparing a beverage

Description:
FIELD OF THE INVENTION 
     The present invention concerns the field of beverage preparations, and especially coffee, by means of infusion machines or apparatuses. 
     In the present application, the term “infusion” refers to a machine or apparatus that allows to produce a beverage, and especially coffee, by means of the passage of a liquid (e.g. water), preferably hot and pressurized, through at least one powder ingredient, especially coffee, which is contained in an infusion chamber. 
     KNOWN PRIOR ART 
     In particular, apparatuses equipped with an infusion chamber (also known in the art as unit or infusion assembly) containing a basic substance or ingredient, typically powdered (such as powdered coffee for example), for preparing a beverage, such as espresso coffee for example, are known. This substance can be arranged directly into the infusion chamber, or can be contained within a container, typically in the form of a capsule, pod or similar element. 
     The apparatus further has a pump and a hydraulic circuit to supply a pressurized liquid to the infusion chamber (typically water) for preparing a beverage. 
     It is also known to divide the preparation and delivery of a beverage into two steps. In particular, it is known to provide a first pre-infusion step of a beverage, in which the heated and pressurized liquid is put in contact with the basic substance inside the infusion chamber, without delivering the beverage from the chamber itself, and a second step in which the real and actual delivery of the beverage occurs. 
     The two steps are typically carried out at least with different pressures of the liquid injected inside the infusion chamber. Thus, systems equipped with variable flow rate and/or pressure pumps, or machines equipped with at least partly different hydraulic ducts to supply liquids with different pressures to the infusion chamber are known. Specific control systems are prearranged to control the various elements of the apparatuses so that to ensure the proper execution of the various beverage preparing and delivering operations. 
     GB 2139481A describes an apparatus for preparing hot coffee beverages which has an hydraulic circuit where the inflow of cold water (A) from the water-supply system divides in two branches: the first branch intended for preparing an espresso coffee and comprising a pressure pump and a second branch bypassing the pump and intended for preparing a normal coffee. A heating unit is arranged just upstream of the infusion assembly. For preparing a normal coffee only the pressure of the water-supply system through the by-pass of the pump is exploited, for preparing an espresso coffee the pump is operated, thus increasing the pressure. The measurement of the delivered water volume and the heating of the water occur, for both modes, by an element controlling the flow and a heating unit in a shared length downstream of the two branches described above and upstream of the inflow valve leading to the delivery unit. 
     WO 2015/055342 describes an apparatus for hot coffee beverages which provides only one circuit whose main components are a pre-heating boiler upstream of an hydraulic pump, a delivery unit provided with a sensor  4  for controlling the temperature, a resistance heater arranged on the infusion assembly and means for weighing the beverage delivered in the cup. The apparatus is provided with a branch bypassing the pump. The operating cycle provides for three steps: a first pre-infusion step which uses the water at the water-supply system pressure through the by-pass, a second under-pressure infusion step which provides for the activation of the pump and a last post-infusion step which provides for the switching off of the pump and the delivery of water to reach the amount/weight parameters required. 
     Such systems are complex to manufacture, use and manage, in particular since the operation time can change due to the deposit of limescale in the circuit. 
     Object of the present invention is to suggest an apparatus and a relative operating method for preparing beverages that is easy to implement and that ensures a good quality of the final beverage. 
     SUMMARY OF THE INVENTION 
     These and other objects are achieved by the present invention according to one or more of the aspects described herein. 
     In particular, the present invention concerns an apparatus and a method according to the independent claims. Preferred aspects are set forth in the dependent claims. 
     In particular, an aspect of the present invention concerns an apparatus for preparing a beverage, comprising: at least one infusion assembly; a hydraulic circuit adapted to connect the infusion assembly with an external water-supply system. The hydraulic circuit defines, for at least one infusion assembly, at least one first fluidic path to connect the infusion assembly to the external water-supply system, and a second fluidic path to connect the infusion assembly to the external water-supply system. The hydraulic circuit provides at least one pump and such at least one pump is arranged on the second fluidic path. The first fluidic path joins the second fluidic path downstream of the pump, to have a portion in common with the second fluidic path downstream of the pump, and the unidirectional-flow control element is arranged on the first path. 
     Thanks to this, the apparatus is able to provide high pressure water to the infusion assembly (by using the pump), or at lower pressure supplied by the external system without operating the pump. In particular, the present apparatus can simply carry out a pre-infusion step, and with low energy consumption, without operating the pump, by exploiting the water pressure supplied by the external system. 
     According to an aspect of the present invention, the unidirectional-flow control element is a valve, preferably a non-return valve. According to an aspect of the present invention, the unidirectional-flow control element is a passively operating element. 
     According to an aspect of the present invention, the unidirectional-flow control element is configured to allow water flow when the upstream pressure is greater than the downstream pressure, and to prevent water flow when the upstream pressure is less than the downstream pressure. 
     This way, the operation of the pump brings pressurized water downstream of the unidirectional-flow control element, which thus prevents water flow in a direction from downstream to upstream, thus closing the first fluidic path. 
     However, when the pump is not operative, the water entering the apparatus from the external source causes the unidirectional-flow control element to open, thus allowing water flow through the first fluidic path. 
     Each infusion assembly has, in a way known per se, a dedicated heating element: preferably, in the first and second circuits there are no other heating means to heat the water for the infusion assembly. Another advantage is that, as mentioned, the heating of the infusion water in the apparatus is carried out by devices localized in each infusion assembly. Thanks to this arrangement, the hydraulic circuits of the apparatus downstream of the infusion assemblies work “in a cold condition” in the supplying steps, thus decreasing or eliminating any limestone production. 
     In a preferred embodiment, the pump serves two or more infusion assemblies; preferably there is only one pump for all the infusion assemblies of the apparatus. For each pump serving two or more infusion assemblies, there is preferably one distribution element (or distribution valve) to which a duct starting from the pump arrives and from which ducts reaching the infusion assemblies extend. The ducts of the first fluidic path meet the ducts of the second fluid path downstream of the pump, thus constituting a by-pass of the latter. In an embodiment the apparatus comprises an electrovalve placed downstream of the pump and upstream of the junction point between the first and the second fluidic paths. Such electrovalve can be controlled by a control unit managing the apparatus operations. 
     In particular, according to a preferred aspect, during a pre-infusion step, the low pressure water (or anyhow at a pressure less than that supplied by the pump during the successive steps of preparing the beverage) coming from the external system opens the first path and reaches the respective infusion assembly. For the circuit concerned, the electrovalve is closed and the non-return valve is open. 
     Thanks to the presence of electrovalves between the pump and the junction point between the first and the second circuits, two coffees can be delivered from two different infusion assemblies and in two different ways. In other words, while an infusion assembly is carrying out a pre-infusion as described above, in the adjoining assembly the infusion and delivery of the beverage can be carried out, with the pump operating. In fact, in the first assembly the electrovalve downstream of the pump is closed, while in the second infusion assembly the electrovalve will be open to connect the pump (shared by the two assemblies) to the second infusion assembly and to deliver the desired beverage. 
     According to an aspect of the present invention, the first path branches off from the second path upstream of the at least one pump, so as to bypass the pump. 
     According to an aspect of the present invention, the hydraulic circuit comprises a volumetric dosing unit to dose the amount of water entering the infusion assembly. 
     According to an aspect of the present invention, the volumetric dosing unit is arranged on the portion shared between the first and the second fluidic path downstream of the pump. 
     According to an aspect of the present invention, the hydraulic circuit comprises a pressure regulator, preferably a pressure reducer, placed on the first path. 
     The pressure regulator is typically a pressure reducer, or anyhow a typically passive element adapted to regulate the pressure entering from the external system. Thus, according to a possible aspect, it is possible to carry out a pre-infusion by exploiting the pressure supplied by the external system, and by using two passive elements (the pressure regulator and the unidirectional-flow control element) to regulate the water pressure and to channel the water flow towards the infusion assembly, so that such pre-infusion step is carried out in a simple and energetically economic way. 
     An aspect of the present invention further concerns a method for preparing a beverage, comprising the steps of: i) connecting an infusion assembly of an apparatus described and/or claimed herein to an external water-supply system; ii) opening the first fluidic path, while keeping the second fluidic path closed, so that the water flows from the external system to the infusion assembly; iii) operating the pump, to bring the water to the infusion assembly, while keeping the first path closed; the water pressure is greater with respect to step ii). 
     According to an aspect of the present invention, the operation of the pump brings pressurized water downstream of the unidirectional-flow control element, so that to prevent the passage of fluid within the first path. 
     According to an aspect of the present invention, the step ii) is a pre-infusion step of the beverage, and wherein the step iii) is a delivering step of the beverage. 
     Lastly, according to a preferred aspect, the duration of step ii) with respect to step iii) can be controlled by the closing and/or opening of an electrovalve placed downstream of the pump and upstream of the junction point between the first and the second fluidic paths, independently for each infusion assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       With reference to the figures attached, exemplary and non-limiting embodiments of the present invention are now introduced, in which: 
         FIG. 1  is a schematic view of an apparatus according to an embodiment of the present invention; 
         FIG. 2  is a detailed view of  FIG. 1 , in which many elements were omitted for simplicity; 
         FIGS. 3 and 4  are views in which the operation of the apparatus, as shown in  FIG. 2 , is schematically shown. 
     
    
    
     METHOD FOR IMPLEMENTING THE INVENTION 
     An apparatus  1  according to the present invention comprises at least one infusion assembly  2   a ,  2   b.    
     There are two infusion assemblies in the embodiment shown. Embodiments, not shown, which are equipped with a single infusion assembly, and also embodiments with a greater number of infusion assemblies, are however possible. In the preferred embodiment shown, the pump of the apparatus is shared by several infusion assemblies. 
     As known, the term infusion assembly (for example a machine for preparing espresso coffee) means a device adapted to receive an input liquid (water in the present invention) for preparing the beverage and to supply an output beverage prepared with such liquid by means of an infusion process. 
     An infusion assembly  2   a ,  2   b  is thus typically equipped with an infusion chamber, in which water meets a basic substance, typically powdered, for preparing a beverage and a nozzle or similar element to allow the delivery of the beverage. As known, for example in the machines for preparing espresso coffee, the infusion assembly, and in particular the infusion chamber, can comprise (or at least partly be constituted by) a filter-holder. A boiler or heater can be provided to heat the water. The infusion chamber can be configured, in a known way, to directly receive a substance, for example powdered, or to receive a container (capsule, pod, or similar element) containing such substance. As mentioned, the infusion chamber can be at least partly constituted by a filter-holder, which is manually connected by the bartender to the machine for preparing espresso coffee. 
     The apparatus  1  further comprises a hydraulic circuit  3  adapted to connect each infusion assembly  2   a ,  2   b  to an external water-supply system  100 . 
     Typically, the hydraulic circuit  3  comprises a plurality of tubes or ducts  3   a , and one or more water flow regulating and/or measuring elements  3   b ,  3   c - 3   c ″,  3   d - 3   d ′,  3   e ,  3   f - 3   f ′. Various water flow regulating and/or measuring elements are known in the art. 
     For example, in a possible embodiment, the hydraulic circuit  3  is equipped with a distributor valve  3   b  adapted to receive water from an inlet and to channel water towards one or more of the outlets connected to it. The valve  3 , or distribution element, is further connected to a boiler for the production of steam  6 , for supplying water to said boiler. 
     According to an aspect, the hydraulic circuit  3  comprises electrovalves  3   c - 3   c ′ adapted to selectively allow and prevent the passage of water through the different ducts  3   a  of the hydraulic circuit  3 . As stated above, the valve  3   c ,  3   c ′ are positioned between the pump  4  and the junction point B, B′ between the first and the second fluidic paths. 
     According to an aspect, the hydraulic circuit comprises manually operated valves  3   d . In the embodiment shown, such manually operated valves  3   d  regulate the inflow of water into the infusion assembly  2   a.    
     According to an aspect, the hydraulic circuit  3  comprises a pressure regulator  3   e , preferably a pressure reducer, adapted to reduce to a predefined value the water pressure entering from the external system  100 , as better discussed below. 
     According to an aspect, the hydraulic circuit  3  comprises a volumetric dosing unit  3   f  upstream of one (and preferably upstream of each) infusion assembly  2   a ,  2   b.    
     In possible embodiments, the hydraulic circuit could be equipped with a combination of some of such elements, and in particular, hydraulic circuits having different combinations of the regulating and measuring elements  3   e - 3   f  are possible. 
     The external system  100  is typically the urban water-supply system. 
     According to a possible aspect shown in the figures, the apparatus  1  (such as for example a machine for preparing espresso coffee) can comprise a boiler  6  for producing steam (typically connected to a respective steam-delivering devices known in the art and not shown in detail). 
     For at least one infusion assembly  2   a ,  2   b , and preferably for each infusion assembly  2   a ,  2   b , the circuit  3  is configured so that to provide a first fluidic path  31  and a second fluidic path  32 . 
     Such first and second fluidic paths  31 ,  32  are shown in detail in  FIG. 2 , with reference to the infusion assembly  2   a . As better discussed below, although not explicitly denoted by numerical references, a first and a second fluidic path having the characteristics discussed herein are also provided for the second infusion assembly  2   b.    
     Both the first and the second fluidic path  31 ,  32  (hereinafter also “first path” and “second path”) are adapted to connect the infusion assembly  2   a  to the external system  100 . 
     There is at least one pump  4 , arranged on the second path  32 , on the circuit  3 . 
     The second path  32  thus allows to supply high pressure water (or anyhow at pressure greater than that supplied by the external system  100 ), while the first path  31  supplies water at the pressure supplied by the external system  100  (possibly modified by the pressure regulator  3   e ). 
     The first and second fluidic paths have at least one portion in common, placed downstream of the pump  4 . The definition “downstream” refers to the path of water inside the second path  32 , from the external system  100  to the infusion assembly  2   a.    
     In particular, the first path  31  is connected to the external system  100  and joins the second path  32  at the junction point B, downstream of the pump  4 . The length between point B and the infusion assembly  2   a  is thus shared between the first path  31  and the second path  32 . 
     The first path  31  comprises a unidirectional-flow control element  5  (hereinafter also named “unidirectional element”  5 ). 
     The term unidirectional-flow control element means an element adapted to allow water flow in one direction, and to prevent water flow in the opposite direction. In other words, the unidirectional element allows the passage of water through the infusion assembly  2   a , but prevents water from crossing the unidirectional element in the opposite direction, i.e. from the infusion assembly  3   a  towards the external system  100 . 
     Preferably, the unidirectional element  5  is passive, i.e. can be operated mechanically. In particular, the state of the unidirectional element (i.e. the opening, to allow the passage of water, and the closing, to prevent the passage of water) can be controlled by a pressure difference, without requiring electric power, or another type of active control/command. 
     Preferably, in fact, when the pressure upstream of the unidirectional element  5  is greater than the pressure downstream of the unidirectional element  5 , the unidirectional element “opens,” i.e. allows the passage of water. Instead, when the pressure downstream of the unidirectional element  5  is greater than the upstream pressure, the unidirectional element “closes,” i.e. preventing the passage of water. The definitions “upstream” and “downstream” refer to a water flow flowing from the external system  100  to the infusion assembly  2   a.    
     The unidirectional element  5  thus allows the passage of water from upstream to downstream, i.e. prevents the passage of water from downstream to upstream. 
     This way, the operation of the pump  4  is sufficient to “close” the unidirectional element, i.e. to bring it to a condition in which it prevents the passage of fluid. 
     In fact, the operation of the pump  4  brings water to the junction point B. At this point, the water (in addition to continuing its path towards the infusion assembly  2   a ) also starts to run through the first path  31  in the opposite direction, until reaching the unidirectional element  5 . As mentioned above, the pressure in the length of the hydraulic circuit comprised between the junction point B and the unidirectional element  5  causes the closing thereof, so that the water cannot cross the unidirectional element, thus preventing it from flowing towards the external system  100 . 
     Preferably, the unidirectional element  5  is a non-return valve. 
     As mentioned above, the first path  31  is connected to the external system  100 . According to a possible aspect, the first path  31  is directly connected to the external system  100 . Preferably, however, as shown in the figures, the first and the second path  31 ,  32  have a further length in common, upstream of the pump  4 . 
     More in detail, the portion between the external system  100  and the branching point A is shared between the first and second path  31 ,  32 . At the branching point A, the first path  31  branches off from the second path  32 , so that the second path  32  passes through the pump  4 , while the first path  31  passes through the unidirectional element  5 , thus avoiding the pump  4 . 
     As described above, the first and the second path  31 ,  32  join at the junction point B. 
     Thus, in other words, the first path  31  preferably provides a bypass of the pump  4 . 
     The first path  31  preferably also has the pressure regulator  3   e  mentioned above. According to an aspect, such pressure regulator  3   e  is placed upstream of the branching point A, i.e. in the portion shared between the first and second path  31 ,  32 . 
     In other possible embodiments, the pressure regulator could be placed on the first path  31  only, for example between the branching point A and the junction point B. 
     In general, the pressure regulator  3   e  is preferably placed on the first path upstream of the junction point B. 
     The pressure regulator  3   e , typically a pressure reducer, is typically a passive element known in the art and configured so that to regulate the pressure of the water entering the apparatus  1  to a predefined value. Such predefined value is typically adjustable, for example manually by a user. 
     With reference to  FIG. 1 , as mentioned above, each infusion assembly  2   a ,  2   b  preferably has a first and a second path. 
     In particular, in the embodiment of  FIG. 1 , the first path for the infusion assembly  2   a  meets the following elements: external system  100 , pressure regulator  3   e , branching point A, unidirectional element  5 , junction point B, volumetric dosing unit  3   f , manually operated valve  3   d , infusion assembly  2   a.    
     The second path for the infusion assembly meets the following elements: external system  100 , pressure regulator  3   e , branching point A, pump  4 , distributor valve  4   b , electrovalve  3   c , junction point B, volumetric dosing unit  3   f , manually operated valve  3   d , infusion assembly  2   a.    
     The first path for the infusion assembly  2   b  meets the following elements: external system  100 , pressure regulator  3   e , branching point A, unidirectional element  5 ′, junction point B′, volumetric dosing unit  3   f , manually operated valve  3   d ′, infusion assembly  2   b.    
     The second path for the infusion assembly  2   b  meets the following elements: external system  100 , pressure regulator  3   e , branching point A, pump  4 , distribution valve  3   b , electrovalve  3   c ′, junction point B′, volumetric dosing unit  3   f , manually operated valve  3   d ′, infusion assembly  2   b.    
     In a preferred embodiment, a further unidirectional element conveniently adjusted can be positioned between the volumetric dosing units  3   f ,  3   f ′ and the valves  3   d ,  3   d ′, respectively, for the infusion assemblies  2   a  and  2   b.    
     With reference to  FIGS. 3 and 4 , the operation of the apparatus  1  is now described, with reference to the infusion assembly  2   a . Such description is generally applied to any infusion assembly of the apparatus  1 . 
     In use, in a first step, preferably a pre-infusion step, water is channeled to the infusion assembly  2   a  without delivering the beverage. Thus, in this step, water fills the infusion chamber and is at a lower pressure than in the successive delivering step. In this step, the pump  4  is not operated. 
     The water coming from the external system  100  (and preferably set at a predefined pressure by the pressure regulator  3   e ) passes through the first path  31 , i.e. through the unidirectional element  5 . 
     With reference to  FIG. 3 , the water branches off from the shared portion at the branching point A and arrives at the unidirectional element. The water pressure opens the unidirectional element  5  so that the water arrives at the junction point B. 
     From here, the water continues its path up to the infusion assembly  2   a . An electrovalve  3   c , or similar regulating and/or measuring element, can be placed on the second path  32  so that to prevent water from flowing from the junction point B towards the pump  4 . 
     Preferably, the amount of water supplied to the infusion assembly  2   a  is monitored by the volumetric dosing unit  3   f , so that to determine when to finish the pre-infusion step. 
     Successively, with particular reference to  FIG. 4 , the pump  4  is operated. If present, the electrovalve  3   c  (or similar regulating and/or measuring element) is opened. This way, the water flows through the second path  32  and is channeled at a greater pressure (with respect to the previous step) to the infusion assembly  2   a.    
     As shown in  FIG. 4  with a dotted arrow, initially the water pressurized by the pump  4  also flows through the length of the first path  31  comprised between the junction point B and the unidirectional element  5 . As described above, the unidirectional element prevents the passage of water through the element itself in that direction. In particular, according to a preferred aspect, the water pressure causes the closing of the unidirectional element  5 , thus preventing water flow through the first path  31 . 
     This way, the water can reach the infusion assembly  2   a  only through the second path, pushed by the pump  4  so that to allow the delivery of a beverage. Preferably, when the volumetric dosing unit  3   f  has detected that the desired amount of water was supplied to the infusion assembly  2   a , the operations of the pump  4  are stopped so that to finish delivering water to the infusion assembly  2   a.    
     By operating the electrovalves  3   c ,  3   c ′ positioned between the pump  4  and each junction point B, B′ between the first and the second fluidic paths, it is possible to contemporaneously deliver two coffees from two different infusion assemblies  2   a ,  2   b , for example. For example, while an infusion assembly  2   a  is carrying out a pre-infusion (ii), in the adjoining assembly  2   b  the infusion and delivery (iii) of the beverage can be carried out, with the pump  4  operating. The pump  4 , as discussed above, can be connected to all of the infusion assemblies. 
     In other word, the beverage is prepared in an apparatus provided with a pump, at least two infusion assemblies and two electrovalves  3   c ,  3   c ′ downstream of said pump on the paths of the circuits of said infusion assemblies  2   a ,  2   b , according to a method comprising the steps of operating the pump  4 ; carrying out a pre-infusion step (ii) for a first infusion assembly  2   a , while keeping the respective electrovalve  3   c  closed of the first path of the circuit of said first infusion assembly; and, at the same time, carrying out the infusion and delivery step (iii) for a second infusion assembly  2   b  by opening the electrovalve  3   c ′ of the first fluidic path of said second delivering assembly.