This present application is a U.S. National Stage Entry of international application PCT/IB2010/002718 filed on Oct. 25, 2010, which in turn is a continuation-in-part of Ser. No. 12/760,555 filed Apr. 15, 2010, and international application PCT/IB2010/002718, filed on Oct. 25, 2010 claims the priority of Italian applications No. PO2099U000011, filed Oct. 23, 2009, and No. PO2010A000004, filed Apr. 15, 2010. The above-identified patent applications are hereby incorporated by reference in their entirety.
The present application claims the priority of Italian applications no. PO2009U000011 and no. PO2010A000004 and of U.S. application Ser. No. 12/760,555, which applications are hereby incorporated by reference in their entirety.
The present invention relates to an improved method and machine for preparing espresso coffee. In particular, the invention relates to a method and to a machine for espresso coffee where the pressure, and in case the temperature, can be changed during coffee brewing.
As is known, brewing espresso coffee requires that a certain amount of water at around 90° C. be forced through a coffee pod at a nominal pressure of around 9 bar.
It is also known that the quality of the espresso is greatly influenced by pressure and temperature. In fact, the physical properties of coffee vary depending on the variety. It follows, therefore, that the parameters for an optimal brew differ for each coffee variety. Prior art machines are ordinarily equipped with a pump driven by an electrical, alternating current motor. Typically the pump is equipped with means for setting the water outlet pressure at the required value. Therefore the pressure cannot be adjusted at the user's will during coffee brewing.
Moreover, the temperature is usually controlled by a heat exchanger, an electromechanical thermostat or an electronic PID temperature controller. At best, these systems provide consistent temperature stability but cannot implement repeatable and customizable temperature profiles.
This invention has for an aim to overcome the above mentioned shortcomings by providing a method and a machine for preparing an espresso coffee where the brewing parameters, in particular water pressure, can be controlled and adjusted by the user. This aim is achieved with a method and a machine according to the accompanying claims.
Experts in the art will better appreciate the technical advantages of the invention from the following description with reference to the accompanying drawings, which illustrate a preferred non-limiting embodiment of it.
In the drawings:
With reference to
According to the invention, as better explained below, each unit 10 is also provided with a user interface (UI), comprising a display 11 and one ore more command buttons 12, and a manual actuator 16 of the pump. For ergonomic reason the manual actuator 16 is preferably located on the brewing group 26.
As illustrated in
The system comprises a control processing unit (CPU), f.i. a microprocessor-based printed circuit board assembly, connected to a pressure control module 22, to a temperature control module 24, in one exemplary embodiment, and to a user interface (UI).
Through the user interface, the user can adjust the extraction pressure—and in case the Temperature—in real time. This is an evident advantage because it allows the user to optimize the brewing parameters according to each different coffee blend used.
The control unit (CPU) comprises a memory and a USB port 18 for connection to an external memory device.
In a first operating mode, the pressure is manually adjusted acting with the lever 16 on the rheostat 15 which changes, through the control processing unit, the speed of the pump 13.
In this operating mode the user can change the pressure as he likes also during brewing of the espresso.
In a second operating mode, different pressure profiles are stored in the control processing unit and called up by the user. A desired pressure profile is selected by the user through the command button 12. The pump 13 is then activated acting on the rheostat 15 through the lever 16. The CPU drives the output of the associated control module—i.e. adjusts the speed of the pump 13 —in such a way as to reproduce the programmed pressure curve.
The different profiles of pressure can be stored in the memory of the CPU by recording the profiles obtained in the manually operated mode. Alternatively, predefined profiles can be downloaded from an external memory device through the USB port. It is also possible to transfer a recorded profile from the CPU to a PC, vary its shape and reload the new profile into the machine.
Three different pressure profiles obtainable according to the invention are shown in
In a further preferred embodiment of the invention, the user can also control the extraction temperature in real time. The temperature profile can therefore be optimized for a particular coffee variety and easily selected through the user interface. In this case too, the CPU can be used to store different temperature profiles to be sent to the associated control module.
The embodiment described above is provided purely by way of an example and it will be understood that other equivalent embodiments are imaginable without departing from the scope of protection of the invention.
Number | Date | Country | Kind |
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PO20090011 U | Oct 2009 | IT | national |
PO2010A0004 | Apr 2010 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IB2010/002718 | 10/25/2010 | WO | 00 | 7/9/2012 |
Publishing Document | Publishing Date | Country | Kind |
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WO2011/055189 | 5/12/2011 | WO | A |
Number | Name | Date | Kind |
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4858522 | Castelli | Aug 1989 | A |
5207148 | Anderson et al. | May 1993 | A |
8367136 | Doglioni Majer | Feb 2013 | B2 |
20070207040 | Hughes et al. | Sep 2007 | A1 |
Number | Date | Country |
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0771542 | May 1997 | EP |
1676509 | Jul 2006 | EP |
1839541 | Oct 2007 | EP |
2027798 | Feb 2009 | EP |
Entry |
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International Search Report dated Jun. 30, 2011 for PCT/IB2010/002718, 3 pp. |
Written Opinion dated Apr. 23, 2012 for PCT/IB2010/002718, 3 pp. |
Number | Date | Country | |
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20120269944 A1 | Oct 2012 | US |
Number | Date | Country | |
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12760555 | Apr 2010 | US |