Automatic machine for making coffee or similar beverages

An automatic machine for making coffee or a similar beverage includes an infusion chamber at atmospheric pressure and adapted to accommodate a mixture of liquid such as hot water and a material serving as the base of the beverage. The infusion chamber has at the bottom thereof a surface permeable to fluids and impermeable to the material. An extraction chamber is positioned below the bottom of the infusion chamber and communicates therewith through the surface. A first control mechanism is positioned within the extraction chamber for moving upwardly therein to force air through the surface into the mixture in the infusion chamber and for moving downwardly within the extraction chamber to extract beverage from the infusion chamber through the surface into the extraction chamber. A second control mechanism is provided within the extraction chamber for forcing beverage within the extraction chamber therefrom under pressure to a dispensing area.

BACKGROUND OF THE INVENTION 
The present invention relates to an automatic machine for making a beverage 
from a liquid such as hot water and a base material such as freshly ground 
coffee. A process and related automatic machine for making coffee in 
measured quantities are disclosed respectively in U.S. Pat. No. 3,552,976 
and U.S. Pat. No. 3,565,641. Coffee is made in accordance with this known 
arrangement by the following sequence. Measured amounts of ground coffee 
and hot water are introduced at atmospheric pressure into an infusion 
chamber equipped at the bottom thereof with an appropriate filter. Air is 
introduced into the infusion chamber through the bottom filter to agitate 
the water/coffee mixture. Brewed coffee is extracted through the filter at 
the bottom of the infusion chamber and is funneled to a dispensing area. 
Particularly, during certain phases of the operating cycle of the machine, 
the bottom of the infusion chamber is hermetically sealed to a lower 
cylinder in which slides a piston. When the piston is moved upwardly 
toward the bottom of the infusion chamber, the piston introduces air 
through the filter into the infusion chamber. When the piston is caused to 
move downwardly the beverage is brewed and extracted through the filter 
due to depressurization. 
Such a solution is advantageous since it allows coffee having particularly 
good organoleptic properties to be made in a short period of time. Such a 
solution however does have certain inconveniences. Particularly, the 
coffee extracted from the infusion chamber must be passed to the 
dispensing area by the force of gravity since the coffee receives no 
positive pressure from the sliding movement of the piston. Therefore, this 
known machine provides limitations as to the relative positioning of the 
various components, since the entire infusion complex must be placed above 
the dispensing area which, for reasons of practicality and 
standardization, also must be located a certain minimum height above the 
floor. This of course also affects the positioning of the other basic 
components of the machine, for example mechanisms necessary to store and 
funnel the ground coffee to the infusion chamber, and possibly also to 
grind the coffee, and the water feed and/or heating mechanisms, unless 
they are designed in a complicated and uneconomical manner. Thus, this 
known coffee machine is undesirably cumbersome and/or insufficiently 
rational with regard to the relative positioning of its various 
components. 
SUMMARY OF THE INVENTION 
Accordingly, an object of the present invention is to provide a machine for 
making coffee or similar beverages automatically, in a short period of 
time, infused at atmospheric pressure and having advantageous organoleptic 
properties, while substantially eliminating the above discussed prior art 
disadvantages. 
It is a further object of the present invention to provide an automatic 
machine for making coffee or similar beverages whereby it is possible to 
dispense the beverage under sufficient pressure without requiring the use 
of complex, costly and/or unreliable devices. 
These objects are achieved in accordance with the present invention by the 
provision of an automatic machine for making coffee or similar beverages 
and including an infusion chamber at atmospheric pressure and adapted to 
accommodate a mixture of a liquid such as hot water and of a material 
serving as the base of the beverage. The infusion chamber has at the 
bottom thereof a surface, such as a filter, permeable to fluids and 
impermeable to the base material. An extraction chamber is positioned 
beneath the bottom of the infusion chamber and communicates therewith 
through the surface. The top of the extraction chamber can be sealed to 
the bottom of the infusion chamber, but the infusion chamber can be 
separated when necessary from the extraction chamber and the surface. A 
first control means is provided within the extraction chamber for moving 
upwardly therein to force air through the surface into the mixture in the 
infusion chamber and for moving downwardly within the extraction chamber 
to extract beverage from the infusion chamber through the surface into the 
extraction chamber. A second control means is positioned within the 
extraction chamber for forcing beverage within the extraction chamber 
therefrom under pressure to at least one dispensing area. Preferably, the 
extraction chamber communicates through the bottom thereof with the 
dispensing area. The second control means is in the form of a piston which 
slides within the extraction chamber from an upper position adjacent the 
surface when the first control means extracts beverage through the surface 
from the control means, successively downwardly toward the bottom of the 
extraction chamber to exert pressure on the beverage therein and to force 
such beverage through the bottom of the extraction chamber to the 
dispensing area.

DETAILED DESCRIPTION OF THE INVENTION 
The machine according to the present invention includes a fixed member 
defining an extraction chamber 6, preferably circular in section. Chamber 
6 includes a middle section 7 of relatively smaller diameter, as well as 
an upper section 8 and a lower section 9 having relatively larger 
diameters. At the bottom of extraction chamber 6 is an opening 10 
connected by a conduit 11 to at least one dispensing area 12 (FIG. 5). The 
dispensing area or member 12 may be positioned at a selected advantageous 
location in the machine, preferably at a position high enough to ensure 
the most convenient use of the machine. 
The top of chamber 6 is closed by a filtering surface 13 which can be in 
the form of a metal and/or paper strip-type filter that additionally may 
be provided with progressive feed and is described in U.S. Pat. No. 
3,565,641. Filtering surface 13 is permeable to fluids and is impermeable 
to a beverage base material, to be described below. 
In a manner to be explained in more detail below, during certain phases of 
the operating cycle of the machine, chamber 6 communicates in a 
hermetically sealed manner via filter surface 13 with an overmounted 
sleeve 14, substantially cylindrical in configuration and open at the top 
thereof to the atmosphere. Sleeve 14 defines an infusion chamber. Sleeve 
14 is connected through an arm 15 to a motorized control component 16 
designed to rotate sleeve 14 in a horizontal plane, in a known manner, 
disengaging sleeve 14 from chamber 6 and filtering surface 13, as shown in 
FIG. 5. When sleeve 14 is in the position shown in FIGS. 1-4, sleeve 14 is 
positioned beneath two feed mechanisms 17, 18 (FIG. 1) designed to supply 
respectively measured quantities of hot water and the material serving as 
the base of the beverage to be made, for example ground coffee, into the 
infusion chamber within sleeve 14. Mechanism 18 must be designed to be 
connected preferably to a reservoir for storing freshly ground coffee, not 
shown for purposes of simplicity of illustration. As indicated above, 
surface 13 is permeablwe to fluids and is impermeable to the material 
serving as the base of the beverage and, under the operating conditions 
shown in FIGS. 1-4, constitutes the bottom of the infusion chamber at 
atmospheric pressure defined within sleeve 14. 
Within cylindrical chamber 6, which is indicated above defines an 
extraction chamber, are placed first and second coaxial and superimposed 
pistons 19, 20. These pistons slide axially in an independent manner 
within chamber 6, with their lateral surfaces substantially fitting the 
inside lateral surface of the middle section 7 of chamber 6. The height 
and cycle of movement of pistons 19, 20 are such that they can slide 
within chamber 6 between two extreme positions, i.e. a resting position as 
shown in FIG. 1 wherein lower piston 19 is within lower widened section 9 
of chamber 6 and piston 20 still cooperates with middle portion 7 of 
chamber 6, and an upper working position shown in FIG. 2 in which piston 
20 is positioned within upper widened section 8 of chamber 6 and piston 19 
still cooperates with middle portion 7 of chamber 6. Pistons 19 and 20 are 
provided with respective piston rods 21, 22. Particularly, piston rod 22 
slides freely within sealed piston rod 21. For this purpose, piston 19 can 
be provided at its top with a rubber ring 23 to form a seal with respect 
to piston rod 22. 
The lower ends of rods 21, 22 opposite respective pistons 19, 20 are formed 
with corresponding lateral projections or similar elements positioned 
side-by-side and formed in a manner similar to that illustrated in FIGS. 
1-5 with respective guide surfaces 24a and 24b, 25. Such guide surfaces 
are designed to cooperate respectively with first and second control pins 
26, 27 that have different lengths and that are attached to a drive chain 
or similar device 28. By means of a series of driving gears drive chain 28 
is made to pass along a curvilinear closed ring configuration, illustrated 
in the drawings, and such driving movement is motorized in a synchronized 
manner with the operation of control component 16. The motorized control 
devices and the reciprocal synchronization device are elements known in 
and of themselves and are not illustrated or described in detail. One 
skilled in the art would understand what types of devices can be employed 
to achieve the illustrated and described operations herein. It 
particularly is contemplated that any known such control and 
synchronization devices can be employed to achieve the movements described 
herein. 
The machine also includes a flexible control such as, for example, a member 
29 having an inclined plane and urged outwardly into an operative position 
by means of a compression spring 30. Inclined plane 29 thus is urged 
outwardly into contact with piston rod 22 of piston 20 and in the upper 
position of piston 20 shown in FIG. 2 operates to maintain such upper 
position. It of course is to be understood that the positioning of control 
member 29 and the calibration of spring 30 are determined according to the 
particular dimensional characteristics of the components of a given 
machine. 
The operation of the machine of the present now will be described. At the 
beginning of each operating cycle the components of the machine are in the 
positions shown in FIG. 1, and infusion chamber 14 is partially filled 
with a mixture of hot water and the material serving as the base for the 
beverage, for example ground coffee, supplied in measured quantities by 
feed mechanisms 17, 18. It is of course to be understood that the 
quantities of the mixture can vary according to the particular 
requirements, for example the content can vary from a single cup to an 
amount for a plurality of cups. Drive chain 28 then is rotated in the 
clockwise direction as illustrated in the drawings, causing control pin 26 
to engage guide surface 24a and to move such guide surface upwardly, 
thereby raising piston 19 and thereby consequently also raising piston 20 
within chamber 6 (FIG. 2). The raising of pistons 19 and 20 causes air to 
be introduced through filter 13 into infusion chamber 14, and such air 
advantageously stirs the mixture of water and ground coffee in a manner in 
and of itself known. When the pistons reach the end of the upper cycle as 
shown in FIG. 2, control member 29 is urged by spring 30 to an outward 
position and cooperates with the bottom of rod 22 to maintain piston 20 in 
its upper position. Pistons 19 and 20 then are maintained stationary in 
such upper positions for a predetermined infusion period. This depends on 
the speed of rotation of chain 28 as well as the geometric characteristics 
thereof and of guide surface 24a while pin 26 disengages from surface 24a. 
When infusion is completed, pin 26 engages guide surface 24b during its 
descending movement, thereby moving piston 19 downwardly, as shown in FIG. 
3. During this phase, piston 20 is maintained at its upper position by 
control member 29 and spring 30. Thus, the downward movement of piston 19 
extracts infused coffee due to depressurization of chamber 14 through 
filter surface 13. Such brewed coffee or other beverage passes through 
filter surface 13 and descends into extraction chamber 16 by passing 
through the annular space between the outer surface of piston 20 and the 
inner surface of upper section 8 of chamber 6. 
When piston 19 reaches the end of its descending cycle it is located within 
lower section 9 of chamber 6, as shown in FIG. 5. At this time, pin 26 is 
disengaged from guide surface 24b. At such time substantially all of the 
measured amount of infused beverage will have been extracted from chamber 
14 into chamber 6. Pin 27 of drive chain 28 then will engage with guide 
surface 25 of piston 20. FIG. 4 shows pin 27 just about to contact surface 
25. When such contact occurs, then piston rod 22 and piston 20 are moved 
downwardly, overcoming the force of spring 30 to retract control member 
29. As shown in FIG. 5, downward movement of piston 20 exerts pressure on 
the underlying measured portion of beverage in extraction chamber 6 and 
thus forces such beverage under pressure through outlet 10 of extraction 
chamber 6 and through conduit 11 to dispensing area 12. The beverage is 
allowed to pass through the annular space between the outer edge of piston 
19 and the inner surface of lower section 9 of chamber 6. 
In accordance with the present invention, it is possible to place the 
dispensing area 12, under which a collection chamber 31 of course is 
provided, at practically any level of the machine, regardless of the 
position of the infusion and extraction chambers. In other words, the 
dispensing area 12 does not need to be located below the extraction 
chamber, since the downward movement of piston 20 forces the brewed 
beverage from the extraction chamber under pressure. Thus, according to 
the present invention it is possible to provide a machine for making 
coffee or similar beverages wherein the functional advantages and simple 
construction known in the trade are maintained, while the relative 
positioning of the various components easily can be optimized. 
Simultaneously with or successive to the phase during which the coffee is 
dispensed (FIG. 5), sleeve 14 is rotated by motorized unit 15, 16 to 
disengage sleeve 14 from filtering surface 13 (which automatically is 
cleaned) and extraction chamber 6 and to empty the used amount of coffee 
32 in a known manner into an appropriate collection area (not shown). 
At the end of the phase in which the coffee is dispensed entirely from 
extraction chamber 6, pistons 19, 20 again are at their respective lower 
positions (as shown in FIG. 1) and sleeve 14 again is brought to position 
over extraction chamber 6. Thus, the machine is ready to begin a new cycle 
to prepare and dispense the beverage. 
It is of course understood that various changes and modifications can be 
made to the described and illustrated arrangement without departing from 
the scope of the present invention. Furthermore, it is to be understood 
that the machine of the present invention can be used to prepare various 
beverages other than coffee, for example tea by use of tea leaves. 
Furthermore, mechanisms 24-30 for control and movement of pistons 19, 20 
can be replaced by any other equivalent structure capable of achieving the 
sequential movements discussed above. One of ordinary skill in the art 
readily would understand what types of other control and synchronizing 
structures can be employed. Still further, one or both of pistons 19, 20 
could be replaced by similar structure to exert the necessary pressure on 
the respective fluids, i.e. air and/or brewed beverage. It particularly is 
contemplated that the pressure to dispense the extracted beverage from 
chamber 6 could be provided by, for example, a conventional pumping 
device, known in and of itself and therefore not illustrated.