Abstract: An automatic machine for preparing coffee beverages includes a brewing unit provided with a brewing chamber connected to a feed circuit for the water by means of an entry aperture and to an exit circuit for the beverage by means of an exit aperture. The machine also includes a valve unit, connected to the exit circuit and configured to supply a first high-pressure exit path and a second low-pressure exit path for the beverage. The invention also concerns a method to prepare a coffee beverage.

Abstract: A valve device suitable to selectively obstruct a flexible tube, includes a first body and a second body operatively associated with each other, which are mobile with respect to each other along a sliding axis, thus configuring an open operating position and a closed operating position and thus defining a passage gap configured to be passed through by the flexible tube. The invention also concerns a machine for preparing beverages which includes a valve device and a corresponding functioning method.

Abstract: A valve device includes an entry aperture and an exit aperture for a fluid, a chamber which puts the entry and exit apertures in selective communication, a housing compartment, a piston disposed in the compartment, which is mobile between a closing position in which it prevents the transit of the fluid and an opening position in which it allows the passage of the fluid, and elastic return means associated with the piston A machine for preparing beverages includes at least one said valve device.

Abstract: Embodiments described here concern a method to control a direct current motor powered by an alternating supply voltage, which provides to detect the instant of the zero-crossing of the supply voltage and to selectively activate a switch device to power the motor by the positive half-waves of the supply voltage in order to make it rotate in one sense, and by the negative half-waves in order to make it rotate in the opposite sense. The disclosure also concerns a control circuit for the motor.

Abstract: A brewing unit for an automatic machine to make coffee beverages includes a brewing chamber closed at the lower part by a first piston and at the upper part, on the opposite side, by a second piston, a first inlet duct for the heated water, and a first outlet duct for the beverage, communicating respectively with an inlet side and with an outlet side of the brewing chamber, and a filtering element disposed in the brewing chamber.

Abstract: Grinding device (1) for an automatic coffee machine, comprising: a support body (2); a lower grinder (3) and an upper grinder (4) arranged coaxially with respect to an axis (X) and delimiting a gap where the grinding is performed; a motor (21) for driving at least one of said grinders (3,4) in rotation about said axis (X); an adjustment ring nut (6) for adjusting the width of said gap having means for transforming a rotation thereof about said axis (X) into a translation of at least one of said grinders in the direction of said axis (X); and a gear for driving said ring nut (6) in rotation; where said gear comprises a toothed wheel arc (7) engaging a pinion (8), and a mechanism for fixing said toothed wheel arc (7) in an adjustable position on said ring nut (6).

Abstract: Grinding device (1) for an automatic coffee machine, comprising: a support body (2); a lower grinder (3) and an upper grinder (4) arranged coaxially with respect to an axis (X) and delimiting a gap where the grinding is performed; a motor (21) for driving at least one of said grinders (3,4) in rotation about said axis (X); an adjustment ring nut (6) for adjusting the width of said gap having means for transforming a rotation thereof about said axis (X) into a translation of at least one of said grinders in the direction of said axis (X); and a gear for driving said ring nut (6) in rotation; where said gear comprises a toothed wheel arc (7) engaging a pinion (8), and a mechanism for fixing said toothed wheel arc (7) in an adjustable position on said ring nut (6).

Abstract: A coffee machine including a controller, an infusion cylinder that can be loaded with a ground coffee dose, an ejection piston slidably supported inside the infusion cylinder, a closing piston engageable in the infusion cylinder to create a closed infusion chamber for the ground coffee dose, delimited between a lateral wall of the infusion cylinder, the ejection piston and the closing piston. Electrical actuation moves the infusion cylinder between a lower travel limit stop, where the ground coffee dose is loaded, and an upper travel limit stop where the infusion process occurs, an adjuster for positioning the upper travel limit stop based on the size of the loaded ground coffee dose, so that in the position of the upper travel limit stop, the infusion chamber has a volume sufficient to contain the ground coffee dose without compressing it.

Abstract: A coffee machine including a controller, an infusion cylinder that can be loaded with a ground coffee dose, an ejection piston slidably supported inside the infusion cylinder, a closing piston engageable in the infusion cylinder to create a closed infusion chamber for the ground coffee dose, delimited between a lateral wall of the infusion cylinder, the ejection piston and the closing piston. Electrical actuation moves the infusion cylinder between a lower travel limit stop, where the ground coffee dose is loaded, and an upper travel limit stop where the infusion process occurs, an adjuster for positioning the upper travel limit stop based on the size of the loaded ground coffee dose, so that in the position of the upper travel limit stop, the infusion chamber has a volume sufficient to contain the ground coffee dose without compressing it.