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.

A method for applying a curable building material, in particular in an additive method, including the steps of: providing at least two separate components of the building material; adding the at least two separate components into a mixing apparatus, in particular into a mixing chamber of the mixing apparatus, by a supply apparatus; mixing the at least two separate components in the mixing apparatus to obtain a curable building material in a set, cured state; supplying the set building material via a conveying line to a printing head, which is movable in at least one spatial direction, using a conveying apparatus; applying the set building material by the movable printing head.

A system for applying a building material including: a mixing device for mixing individual components of the building material into a curable building material; a pressure head which can be moved in at least one spatial direction and by means of which the workable building material can be applied; a delivery line, with which the curable building material can be conveyed from the mixing device to the pressure head; at least one delivery device for delivering the curable building material from the mixing device through the delivery line to the pressure head; a feed device, which is designed in such a manner that at least two separate components of the building material can be fed via at least two separate inlets into the mixing device, more particularly into a mixing chamber of the mixing device.

A system for applying a building material including: a mixing device for mixing individual components of the building material into a curable building material; a pressure head which can be moved in at least one spatial direction and by means of which the workable building material can be applied; a delivery line, with which the curable building material can be conveyed from the mixing device to the pressure head; at least one delivery device for delivering the curable building material from the mixing device through the delivery line to the pressure head; a feed device, which is designed in such a manner that at least two separate components of the building material can be fed via at least two separate inlets into the mixing device, more particularly into a mixing chamber of the mixing device.

A piston-rod unit for a hydraulic cylinder including a first end piece that is a piston-side end piece and a second end piece that is a rod-eye-side end piece. The piston-rod unit also includes a hollow piston rod with a cavity and that is arranged between the first end piece and the second end piece. The cavity extends at least partially into one or both of the first end piece and the second end piece. A plug is inserted into the cavity such that the plug supports the piston rod and/or the first end piece or second end piece.

A vehicle having a thick matter pump has multiple supporting devices, a rotatable mast assembly with part-mast members, and a hydraulic drive assembly with hydraulic drives for the supporting devices and the mast assembly. A valve assembly is provided for the hydraulic drive assembly. The valve assembly has a group of proportional valves and a group of switching valve devices which are each connected to at least one hydraulic drive of the supporting devices or the part-mast members. The switching valve devices are connected downstream of the proportional valves. Exactly one switching valve device is supplied by exactly one proportional valve and is connected downstream of exactly one proportional valve such that outputs of the proportional valves lead exclusively to inputs of the switching valve devices.

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.

A hydraulic system (600) and method for reducing boom dynamics of a boom (30), while providing counter-balance valve protection, includes a hydraulic cylinder (110), first and second counter-balance valves (300, 400), and first and second control valves (700, 800). A net load (90) is supported by a first chamber (116, 118) of the hydraulic cylinder, and a second chamber (118, 116) of the hydraulic cylinder may receive fluctuating hydraulic fluid flow from the second control valve to produce a vibratory response (950) that counters environmental vibrations (960) on the boom. The first control valve may apply a holding pressure and thereby hold the first counter-balance valve closed and the second counter-balance valve open.

A hose management system for a 3D printing system having a print medium pump and a print nozzle may include a base, a vertical tower extending upward from the base, a vertical pipe rotatably coupled to the vertical tower, a boom pipe extending laterally outward from and rotating with the vertical pipe, a stick connected to the boom pipe for relative rotation about at least two perpendicular axes, and a print hose connected between the boom pipe and the print nozzle so that the vertical pipe, the boom pipe and the print hose place the print medium pump in fluid communication with the print nozzle. The print hose may be suspended from the stick such that the vertical pipe, the boom pipe, the stick and the print hose follow movement of the print nozzle by the 3D printing system to print a 3D object.

A vehicle having a thick matter pump has multiple supporting devices, a rotatable mast assembly with part-mast members, and a hydraulic drive assembly with hydraulic drives for the supporting devices and the mast assembly. A valve assembly is provided for the hydraulic drive assembly. The valve assembly has a group of proportional valves and a group of switching valve devices which are each connected to at least one hydraulic drive of the supporting devices or the part-mast members. The switching valve devices are connected downstream of the proportional valves. Exactly one switching valve device is supplied by exactly one proportional valve and is connected downstream of exactly one proportional valve such that outputs of the proportional valves lead exclusively to inputs of the switching valve devices.