Certain examples described herein relate to a removable unit for a three dimensional printing system. The removable unit comprises at least one compartment to store build material for a three-dimensional print job, a coupling to engage with a printer device of the three-dimensional printing system, and a memory. The memory is configured to store instructions for the three-dimensional print job for the printer device, and the instructions are readable from the memory by the printer device when the removable unit is engaged with the printer device.

Certain examples described herein relate to a removable unit for a three dimensional printing system. The removable unit comprises at least one compartment to store build material for a three-dimensional print job, a coupling to engage with a printer device of the three-dimensional printing system, and a memory. The memory is configured to store instructions for the three-dimensional print job for the printer device, and the instructions are readable from the memory by the printer device when the removable unit is engaged with the printer device.

The present disclosure describes a 3D printer comprising a core exchanger mechanism to store filament cores, a hotend, an actuation arm and a cutting mechanism to sever the filament. The cores are swappable by the core exchanger mechanism to provide a variety of filament to the 3D printed object during printing. A coreless hotend for use with a 3D printer is also provided, comprised of a receptacle to receive and store cores of the 3D printer during 3D printing. The coreless hotend is also comprised of a locking mechanism to lock and release the cores from the receptacle to replace the core with another core.

The present disclosure describes a 3D printer comprising a core exchanger mechanism to store filament cores, a hotend, an actuation arm and a cutting mechanism to sever the filament. The cores are swappable by the core exchanger mechanism to provide a variety of filament to the 3D printed object during printing. A coreless hotend for use with a 3D printer is also provided, comprised of a receptacle to receive and store cores of the 3D printer during 3D printing. The coreless hotend is also comprised of a locking mechanism to lock and release the cores from the receptacle to replace the core with another core.

Build material handling unit (2) for a powder module (3) for an apparatus for additively manufacturing three-dimensional objects, which apparatus is adapted to successively layerwise selectively irradiate and consolidate layers of a build material (4) which can be consolidated by means of an energy source, wherein the build material handling unit (2) is coupled or can be coupled with a powder module (3), wherein the build material handling unit (2) is adapted to level and/or compact a volume of build material (4) arranged inside a powder chamber (5) of the powder module (3) by controlling the gas pressure inside the powder chamber (5).

Apparatus (1) for additively manufacturing of three-dimensional objects by means of successive layerwise selective irradiation and consolidation of layers of a build material which can be consolidated by means of an energy beam, with a stream generating unit (2) configured to generate a stream of a process gas (3) being capable of being charged with particles (4), in particular non-consolidated particulate build material and/or smoke and/or smoke residues, generated during operation of the apparatus (1) and a filter unit (5) configured to separate particles (4) from the stream of process gas (3), wherein the filter unit (5) comprises a filter chamber (6) with at least one filter element (7) at least partly arranged in the streaming path of the generated stream of process gas (3), wherein particles (4) in the stream of process gas (3) are separated from the process gas (3) by the filter element (7), wherein a particle reception chamber (13, 26, 28) is separably connected or connectable to a particle outlet (11) of the filter chamber (6) and configured to receive the particles (4) separated from the process gas (3).

Apparatus (1) for additively manufacturing of three-dimensional objects by means of successive layerwise selective irradiation and consolidation of layers of a build material which can be consolidated by means of an energy beam, with a stream generating unit (2) configured to generate a stream of a process gas (3) being capable of being charged with particles (4), in particular non-consolidated particulate build material and/or smoke and/or smoke residues, generated during operation of the apparatus (1) and a filter unit (5) configured to separate particles (4) from the stream of process gas (3), wherein the filter unit (5) comprises a filter chamber (6) with at least one filter element (7) at least partly arranged in the streaming path of the generated stream of process gas (3), wherein particles (4) in the stream of process gas (3) are separated from the process gas (3) by the filter element (7), wherein a particle reception chamber (13, 26, 28) is separably connected or connectable to a particle outlet (11) of the filter chamber (6) and configured to receive the particles (4) separated from the process gas (3).

A print material cartridge may include a hopper to maintain an amount of print material therein; and an atmospheric pressure seal to seal the hopper from atmosphere; wherein a pressure within the hopper and sealed by the atmospheric pressure seal is lower than atmosphere.

Examples of the present disclosure relate to a container. The container has a chamber for storing build material for a three-dimensional printing system. The container comprises an opening coaxial with the chamber for coupling to the three-dimensional printing system. The container is configured such that rotation of the chamber in a first direction conveys build material in the chamber to the three-dimensional printing system and rotation of the chamber in a second direction conveys the build material away from the three-dimensional printing system.

Examples of the present disclosure relate to a container. The container has a chamber for storing build material for a three-dimensional printing system. The container comprises an opening coaxial with the chamber for coupling to the three-dimensional printing system. The container is configured such that rotation of the chamber in a first direction conveys build material in the chamber to the three-dimensional printing system and rotation of the chamber in a second direction conveys the build material away from the three-dimensional printing system.