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.

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 cover 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 cover element is designed to cover at least a part of the discharge opening such that an opening cross section of at least one uncovered part of the discharge opening specifies a strand cross section of the discharged strand of building material.

An apparatus for making and depositing bricks includes a nozzle having an inlet opening, an outlet opening, and a plurality of walls surrounding the outlet opening. At least one of the walls is configured to retract relative to the other walls. When a first brick is deposited, all of the nozzle walls are in the extended position. When subsequent bricks are deposited, one or more of the nozzle walls are retracted so that the form for the subsequent bricks is provided by the walls that are in the extended position and the sides of the already-deposited bricks. In this manner, the nozzle is configured to deposit the bricks directly adjacent to each other without any space or intervening material between them. The bricks may be deposited in a heated state and they meld together as they cool. The nozzle is particularly advantageous for paving autonomously in otherwise inaccessible locations, such as surfaces on the moon or other planets.

A method for producing a honeycomb structure includes: a forming step of extruding a forming raw material containing a ceramic raw material to obtain a honeycomb formed body, the honeycomb formed body including: an outer peripheral wall; and partition walls disposed on an inner side of the outer peripheral wall, the partition walls defining a plurality of cells, each of the plurality of cells extending from one end face to the other end face to form a flow passage; a drying step of drying the honeycomb formed body to obtain a honeycomb dried body; and a firing step of firing the honeycomb dried body to obtain a honeycomb fired body. The forming step includes extruding the forming raw material to produce a honeycomb formed body in which a part of the partition walls is lost so that some of the cells are connected to each other.

A system for controlling center-to-outer flow distribution of extrudate source material through an extrusion die suitable for production of a honeycomb extrudate, and a method for fabricating a honeycomb extrudate, are provided. Sequentially arranged first and second plates define first and second pluralities of openings through which extrudate source material may flow, wherein at least some openings of the second plurality of openings arranged at different radial positions differ in area. Relative movement between the first plate and the second plate may be effectuated to adjust overlap between corresponding openings of the plates, thereby adjusting a center-to-outer flow distribution of extrudate source material through an extrusion die arranged downstream of the first and second plates.

An apparatus for making and depositing bricks includes a nozzle having an inlet opening, an outlet opening, and a plurality of walls surrounding the outlet opening. At least one of the walls is configured to retract relative to the other walls. When a first brick is deposited, all of the nozzle walls are in the extended position. When subsequent bricks are deposited, one or more of the nozzle walls are retracted so that the form for the subsequent bricks is provided by the walls that are in the extended position and the sides of the already-deposited bricks. In this manner, the nozzle is configured to deposit the bricks directly adjacent to each other without any space or intervening material between them. The bricks may be deposited in a heated state and they meld together as they cool. The nozzle is particularly advantageous for paving autonomously in otherwise inaccessible locations, such as surfaces on the moon or other planets.

In a method of manufacturing objects, extrudable ceramic forming material is extruded through multiple dies arrayed around an extrusion axis, the dies mounted to permit controlled movement of the dies during the course of extrusion to vary the position of several extrudate streams exiting the dies. Extruded objects are defined by spokes corresponding to the extrudate streams with the streams having a varying spacing from a central axis.

An apparatus for making and depositing bricks includes a nozzle having an inlet opening, an outlet opening, and a plurality of walls surrounding the outlet opening. At least one of the walls is configured to retract relative to the other walls. When a first brick is deposited, all of the nozzle walls are in the extended position. When subsequent bricks are deposited, one or more of the nozzle walls are retracted so that the form for the subsequent bricks is provided by the walls that are in the extended position and the sides of the already-deposited bricks. In this manner, the nozzle is configured to deposit the bricks directly adjacent to each other without any space or intervening material between them. The bricks may be deposited in a heated state and they meld together as they cool. The nozzle is particularly advantageous for paving autonomously in otherwise inaccessible locations, such as surfaces on the moon or other planets.

A system for controlling center-to-outer flow distribution of extrudate source material through an extrusion die suitable for production of a honeycomb extrudate, and a method for fabricating a honeycomb extrudate, are provided. Sequentially arranged first and second plates define first and second pluralities of openings through which extrudate source material may flow, wherein at least some openings of the second plurality of openings arranged at different radial positions differ in area. Relative movement between the first plate and the second plate may be effectuated to adjust overlap between corresponding openings of the plates, thereby adjusting a center-to-outer flow distribution of extrudate source material through an extrusion die arranged downstream of the first and second plates.

In a method of manufacturing objects, extrudable ceramic forming material is extruded through multiple dies arrayed around an extrusion axis, the dies mounted to permit controlled movement of the dies during the course of extrusion to vary the position of several extrudate streams exiting the dies. Extruded objects are defined by spokes corresponding to the extrudate streams with the streams having a varying spacing from a central axis.