Machine and method for producing and delivering coffee-based beverages
A machine is described, for producing and delivering coffee-based beverages comprising: a heating boiler ( 1 ); a delivering assembly ( 3 ) comprising a solenoid valve ( 8 ) and second means for heating ( 7 ) and controlling ( 4 ) the water temperature; a filter-holder ( 5 ) removably connectable to the delivering assembly ( 3 ), comprising a filter ( 6 ) in which the powder of ground coffee is pressed; a hydraulic pump ( 2 ) for delivering water from the delivering assembly ( 3 ) through the powder of ground coffee, and connected to the heating boiler ( 1 ) and to the delivering assembly ( 3 ); a first pressure sensor ( 21 ) to detect the water delivery pressure and regulate the flow-rate of water depending on the pressure value detected by a second pressure sensor ( 26 ) arranged next to the solenoid valve ( 8 ) to measure the counter-pressure exerted by the powder of ground coffee.
1 . A machine for producing and delivering coffee-based beverages comprising:
a heating boiler comprising first means for heating and controlling a water temperature;
a delivering assembly comprising a solenoid valve and second means for heating and controlling the water temperature for heating water;
a filter-holder removably connectable to the delivering assembly, comprising a filter in which the powder of ground coffee is pressed;
a hydraulic pump configured for delivering water from the delivering assembly through the pressed powder of ground coffee contained in the filter of the filter-holder, and connected in fluid communication through a hydraulic circuit to the heating boiler and to the delivering assembly; and
a first pressure sensor arranged along the hydraulic circuit to detect a delivery pressure of the water supplied by the hydraulic pump,
wherein the flow-rate of water delivered by the pump is varied based on the delivery pressure detected by the first pressure sensor;
a second pressure sensor that is hydraulically connected between the solenoid valve and the filter-holder, the second pressure sensor being configured to measure a counter-pressure exerted by the pressed powder of ground coffee in the filter; and
an electronically controlled regulating valve to regulate the flow-rate of water from the hydraulic pump delivered by the delivering assembly based on (i) the delivery pressure measured by the first pressure sensor and (ii) the counter-pressure measured by the second pressure sensor,
such that, during beverage preparation, the measured counter-pressure exerted by the powder of ground coffee contained in the filter is controlled, as well as the flow rate of water delivered by the hydraulic pump.
2 . The machine of claim 1 , wherein the regulating valve is part of a means for regulating the flow-rate arranged in a manifold along the hydraulic circuit to regulate flow-rate and pressure of water delivered by the delivering assembly depending on the counter-pressure measured by the second pressure sensor.
3 . The machine of claim 1 , wherein the regulating valve has a variable and adjustable flow-rate and is arranged between the heating boiler and the delivering assembly.
4 . The machine of claim 3 , wherein the regulating valve with adjustable flow-rate is an electronically controlled proportional solenoid valve.
5 . The machine of claim 1 , wherein the heating boiler is supplied through the hydraulic network by interposing a sweetener, a filter and a manifold whose function is dispensing the network water in the hydraulic circuit.
6 . The machine of claim 1 , wherein the heating boiler is connected to the delivering assembly through a volumetric meter to manage an amount of delivered coffee.
7 . A method for producing and delivering coffee-based beverages with a machine according to claim 1 , wherein the method comprises the steps of:
raising the water temperature, inside the heating boiler and inside the delivering assembly to regulate delivered thermal power; and
a step of delivering water from the delivering assembly, in order to obtain an infusion of the powder of ground coffee pressed in the filter contained in the filter-holder by regulating the flow-rate of water delivered through the regulating valve to obtain a dose of the coffee-based beverage based on the counter-pressure measured by the second pressure sensor.