There is provided a liquid discharge head, including: a pressure chamber connected to a nozzle from which a liquid is discharged; an actuator configured to apply discharge pressure to the liquid in the pressure chamber; a first supply channel which is connected to the pressure chamber, and through which a first liquid is supplied to the pressure chamber; a second supply channel, different from the first channel, which is connected to the pressure chamber, and through which a second liquid different from the first liquid is supplied to the pressure chamber; a first valve which is disposed in the first supply channel, and by which the first supply channel is opened and closed; and a second valve which is disposed in the second supply channel, and by which the second supply channel is opened and closed.

A valve jet printer includes a solenoid coil and a plunger rod having a magnetically susceptible shank. A first end of the shank and at least a portion of the shank are received within a bore of the solenoid coil. The printer also includes a nozzle including an orifice extending therethrough and a spring biasing a second end of the shank toward the nozzle. The second end of the plunger rod includes a tip formed of perfluoroelastomer (FFKM). The second end of the shank includes a cup-shaped cavity having a convex bottom and a circular side. The tip includes a concave base and an annular flange. In an assembled state, the concave base of the tip contacts the convex bottom of the cup-shaped cavity, and the end of the circular side opposite the convex bottom is rolled over the annular flange thereby securing the tip in the cup-shaped cavity.

A liquid discharge device includes a head including a discharge port. The head discharges a liquid from the discharge port toward an object. The liquid discharge device further includes a liquid receiving surface to receive the liquid discharged from the discharge port, a liquid collector to collect the liquid received by the liquid receiving surface, and a moving unit to hold the liquid receiving surface and the liquid collector. The moving unit is movable at a facing position where the liquid receiving surface faces the discharge port without changing an inclination of the liquid collector with respect to a horizontal plane.

A liquid discharge apparatus includes a head to discharge a liquid containing a solvent from a discharge port toward an object, a concentration detector to detect a vapor concentration of the solvent, and circuitry to causes the head to discharge the liquid from the discharge port while moving the discharge port of the head in a movement direction perpendicular to a discharge direction to discharge the liquid. When the vaper concentration is equal to or higher than a first threshold, the circuitry stops moving the head in the movement direction and causes the head to stop discharging the liquid from the discharge port. When the vaper concentration is less than a second threshold, the circuitry resumes moving the head in the movement direction from a stop position where the head stops moving in the movement direction and causes the head to resume discharging the liquid from the discharge port.

A liquid discharge apparatus includes a head including a discharge port. The head discharges a liquid from the discharge port toward an object. The liquid discharge apparatus further includes a liquid receiving surface that receives the liquid discharged from the discharge port, a contact part that contacts the discharge port, a moving unit that holds at least one of the liquid receiving surface and the contact part, and a holder. The moving unit is movable between a facing position where at least one of the liquid receiving surface and the contact part faces the discharge port and a position where the liquid receiving surface and the contact part do not face the discharge port. The holder movably holds the discharge port of the head in a discharge direction to discharge the liquid.

A jetting device configured to jet one or more droplets of a viscous medium through the outlet of a nozzle includes an energy output device. The energy output device is configured to direct a quantum of energy into at least a portion of the volume of the viscous medium jetted through the outlet to control a breaking of the droplet from the nozzle. The energy output device may include an acoustic transducer or a piezoelectric material or a laser emitter or a heater.

An image forming apparatus includes a linehead and a control unit. The linehead of an image forming apparatus includes a common ink chamber, a plurality of nozzles, an individual ink flow path, an ink supply path, a first piezoelectric actuator, and a second piezoelectric actuator. One end of the individual ink flow path is connected to the nozzle. The ink supply path is connected to the individual ink flow path and the common ink chamber. When putting the nozzle into a drying prevention state, the control unit deforms the first piezoelectric actuator in a direction in which a capacity of the individual ink flow path increases, to thereby draw an interface of ink to inside the nozzle. Further, the control unit deforms the second piezoelectric actuator, to thereby close the ink supply path.

A pressure adjustment unit includes a valve body including a base end portion, a shaft portion protruding in a first-direction from the base end portion, and an elastic member, and a casing that has a partition wall formed with a through hole into which the shaft portion is inserted, and a first-wall protruding in a second-direction opposite to the first-direction to define the first-chamber. On a first-chamber side of the partition wall, a valve seat, which is annular, is provided around the through hole to block a flow path by contacting with the elastic member, an outer periphery of the base end portion has a positioning region, and a distance between a first-direction-side end portion of the positioning region and a first-direction-side distal end of the shaft portion is shorter than a distance between the valve seat and a second-direction-side end portion of the first-wall.

The invention relates to a piston (5) for a printhead (1) of a 3D printer, particularly a metal printer, comprising a piston rod (17) and a ram (18), the ram (18) having a discharge side (19) that has a convex or tapering surface (39). The invention also relates to a printhead (1) for a 3D printer, particularly a metal printer, comprising a housing (3), a device (28) for supplying a metal (14), a reservoir (7, 27) for a liquid phase (8) of the metal (14), a nozzle device (2) comprising a guide sleeve (11) and a nozzle plate (9), and a piston (5) according to one of the preceding claims, the ram (18), the guide sleeve (11) and the nozzle plate (9) forming a displacement chamber (21), and the ram (18) and the guide sleeve (11) forming at least one area (40) for conducting the liquid phase (8) between the reservoir (27) and the displacement chamber (21).

A printing device for building material articles, comprises a tank (2) for a printing material, solid or liquid, to be dispensed, an outlet mouth (3) suitable for dispensing the printing material onto a work surface, a conduit (5) extending along its own main direction (A) between the tank (2) and the outlet mouth (3), in which the conduit (5) comprises at least one deformable wall (6) movable between an operating position, in which it determines the creation of a restriction in the conduit (5) preventing the flow of the printing material towards the outlet mouth (3), and a rest position, in which it allows the flow of the printing material towards the outlet mouth (3).