The invention relates to a device (100) for the additive manufacture of three-dimensional workpieces, in particular a 3D metal printer, comprising a print head (1) and a device (40) for generating an inert atmosphere (22) within the print head (1) by means of a gas (55), in particular inert gas, wherein the print head (1) comprises a housing (3), a device (28) for feeding a metal (14), a piston (5), a reservoir (7) with an outlet opening (10) and an actuator device (12) for displacing the piston (5), wherein the reservoir (7) has a melt region (20) and a displacement body chamber (21) for a liquid phase (8) of the metal (14), wherein the melt region (20) adjoins the inert atmosphere (22) and is connected to the displacement body chamber (21) such that, as a result of the displacement of the piston (5), the liquid phase (8) of the metal (14) can be caused to pass through the outlet opening (10). The invention is distinguished by the fact that the device (40) for generating the inert atmosphere (22) is arranged outside the print head (1), wherein said device comprises an accumulator (41), at least one means (42, 43) for pressure control, and a gas line (50, 51, 52). The invention furthermore relates to methods for operating the device (100).

The invention relates to a device (100) for the additive manufacture of three-dimensional workpieces, in particular a 3D metal printer, comprising a print head (1) and a device (40) for generating an inert atmosphere (22) within the print head (1) by means of a gas (55), in particular inert gas, wherein the print head (1) comprises a housing (3), a device (28) for feeding a metal (14), a piston (5), a reservoir (7) with an outlet opening (10) and an actuator device (12) for displacing the piston (5), wherein the reservoir (7) has a melt region (20) and a displacement body chamber (21) for a liquid phase (8) of the metal (14), wherein the melt region (20) adjoins the inert atmosphere (22) and is connected to the displacement body chamber (21) such that, as a result of the displacement of the piston (5), the liquid phase (8) of the metal (14) can be caused to pass through the outlet opening (10). The invention is distinguished by the fact that the device (40) for generating the inert atmosphere (22) is arranged outside the print head (1), wherein said device comprises an accumulator (41), at least one means (42, 43) for pressure control, and a gas line (50, 51, 52). The invention furthermore relates to methods for operating the device (100).

Techniques for debinding additively fabricated parts are described that do not require solvent debinding or catalytic debinding, and that may be performed using only thermal debinding in a furnace. As a result, in at least some cases debinding and sintering may take place sequentially within a single furnace. In some embodiments, the techniques may utilize particular materials as binders that allow for a thermal debinding process that does not negatively affect the parts.

Techniques for debinding additively fabricated parts are described that do not require solvent debinding or catalytic debinding, and that may be performed using only thermal debinding in a furnace. As a result, in at least some cases debinding and sintering may take place sequentially within a single furnace. In some embodiments, the techniques may utilize particular materials as binders that allow for a thermal debinding process that does not negatively affect the parts.

An example additive manufacturing system comprises a first fan associated with a print chamber to flow gas from the print chamber into an exhaust conduit. A sensor is arranged to detect one or more conditions of the gas flowed into the exhaust conduit from the print chamber by the first fan and to output a signal indicative thereof. A second fan is spaced apart in a downstream direction along the exhaust conduit from the first fan and a control unit is arranged to receive the signal from the sensor and to control the second fan in dependence thereon to maintain one or more conditions of the gas extracted from the print chamber.

An example additive manufacturing system comprises a first fan associated with a print chamber to flow gas from the print chamber into an exhaust conduit. A sensor is arranged to detect one or more conditions of the gas flowed into the exhaust conduit from the print chamber by the first fan and to output a signal indicative thereof. A second fan is spaced apart in a downstream direction along the exhaust conduit from the first fan and a control unit is arranged to receive the signal from the sensor and to control the second fan in dependence thereon to maintain one or more conditions of the gas extracted from the print chamber.

A 3D printing system comprises a pressure system to provide a negative pressure and a hopper having a first opening to receive powder to be used for printing, wherein the powder is received in an open state of the first opening. The hopper has a second opening to guide air from outside the hopper to inside the hopper and has a third opening connected to the pressure system so as to provide for a negative pressure inside the hopper, the negative pressure to overcompensate for the air receive through the second opening such that a pressure being lower when compared to an ambient pressure of the hopper is generated inside the hopper.

A 3D printing system comprises a pressure system to provide a negative pressure and a hopper having a first opening to receive powder to be used for printing, wherein the powder is received in an open state of the first opening. The hopper has a second opening to guide air from outside the hopper to inside the hopper and has a third opening connected to the pressure system so as to provide for a negative pressure inside the hopper, the negative pressure to overcompensate for the air receive through the second opening such that a pressure being lower when compared to an ambient pressure of the hopper is generated inside the hopper.

Provided is a laminate molding apparatus including a chamber, a laser irradiation device, an inert gas supply device, a fume collector, and an evacuate device. The evacuate device includes an intake port, an evacuate amount adjusting portion, a controller, and an evacuate port. The intake port is connected to any part of the laminate molding apparatus through which the inert gas flows, and takes in the inert gas. The evacuate amount adjusting portion adjusts an evacuate amount of the inert gas. The controller controls the evacuate amount adjusting portion to evacuate the inert gas such that an atmospheric pressure in the chamber and an external atmospheric pressure become uniform within a range in which leakage of the inert gas from the chamber is suppressed. The evacuate port evacuates the inert gas from which fumes have been removed to the outside of the laminate molding apparatus.

Provided is a laminate molding apparatus including a chamber, a laser irradiation device, an inert gas supply device, a fume collector, and an evacuate device. The evacuate device includes an intake port, an evacuate amount adjusting portion, a controller, and an evacuate port. The intake port is connected to any part of the laminate molding apparatus through which the inert gas flows, and takes in the inert gas. The evacuate amount adjusting portion adjusts an evacuate amount of the inert gas. The controller controls the evacuate amount adjusting portion to evacuate the inert gas such that an atmospheric pressure in the chamber and an external atmospheric pressure become uniform within a range in which leakage of the inert gas from the chamber is suppressed. The evacuate port evacuates the inert gas from which fumes have been removed to the outside of the laminate molding apparatus.