Abstract: An extruder apparatus for the extrusion of a strand of building material for 3D printing of a structural part includes an extruder nozzle and at least one inner element. The extruder nozzle has a discharge opening for the discharge of the strand of building material out of the extruder apparatus. The at least one inner element is designed for arrangement within the extruder nozzle for purposes of defining an inner edge of a flow cross section of building material within the extruder nozzle in order to specify an inner edge of a strand cross section of the discharged strand of building material.

Abstract: An energy supply device for supplying electric loads with electric energy, includes a DC link; a first mains connection to which a first AC voltage grid can be connected as intended; a first rectifier which is designed to rectify an AC voltage corresponding to an AC voltage across the first mains connection or based thereon and to feed the rectified voltage into the DC link; a second mains connection to which a second AC voltage grid can be connected as intended; a second rectifier which is designed to rectify an AC voltage corresponding to an AC voltage across the second mains connection or based thereon; a controllable DC-to-DC converter to a first side of which a voltage rectified by means of the second rectifier is applied, and a second side of which is connected to the DC link; a first current converter which is fed from the DC link and is designed to supply a first electric load with electric energy; a power measuring apparatus which is designed to measure electric power consumed at the first mains conn

Abstract: An energy supply device for supplying electric loads with electric energy, includes a DC link; a first mains connection to which a first AC voltage grid can be connected as intended; a first rectifier which is designed to rectify an AC voltage corresponding to an AC voltage across the first mains connection or based thereon and to feed the rectified voltage into the DC link; a second mains connection to which a second AC voltage grid can be connected as intended; a second rectifier which is designed to rectify an AC voltage corresponding to an AC voltage across the second mains connection or based thereon; a controllable DC-to-DC converter to a first side of which a voltage rectified by means of the second rectifier is applied, and a second side of which is connected to the DC link; a first current converter which is fed from the DC link and is designed to supply a first electric load with electric energy; a power measuring apparatus which is designed to measure electric power consumed at the first mains conn

Abstract: An extruder apparatus for the extrusion of a strand of building material for 3D printing of a structural part includes an extruder nozzle and at least one inner element. The extruder nozzle has a discharge opening for the discharge of the strand of building material out of the extruder apparatus. The at least one inner element is designed for arrangement within the extruder nozzle for purposes of defining an inner edge of a flow cross section of building material within the extruder nozzle in order to specify an inner edge of a strand cross section of the discharged strand of building material.

Abstract: An extruder head for extruding a strand of building material for 3D printing of a structural part. The extruder head has an extruder nozzle with a discharge opening for discharging the strand of building material out of the extruder head in a discharge direction, a specification element designed to be variably adjustable for variably settably specifying at least a part of a strand cross section of the strand of building material being discharged, and a setting apparatus designed for variably setting the at least one specification element. The setting apparatus is designed and arranged such that the extruder head, in a first extent direction which differs from the discharge direction, extends below the discharge opening, in the case of a maximum opening height, by at most the maximum opening height, and/or, in at least one second extent direction differing from the discharge direction, extends to the side of the discharge opening, in the case of a maximum opening width, by at most the maximum opening width.