Abstract: Apparatus for mixing charges of flowable solid materials has a hollow cylindrical housing with two upright end walls and a hollow shell between the end walls. The lower part of the shell has a large material evacuating opening sealable by two mirror symmetrical doors which are pivotable about horizontal axes. The opening extends all the way between the end walls and is large enough to allow for gravitational outflow of the entire contents of the housing irrespective of the angle of repose of the charge. The doors are bounded by edge faces which make oblique angles with their external surfaces and abut against complementary edge faces of the end walls and shell. Sealing strips on the shell and end walls are engaged by deforming members at the external surfaces of the doors when the opening is closed. The abutting edge faces of the doors also make oblique angles with the respective external surfaces.

Abstract: Mixing apparatus is provided for the production of mixtures of particulate solids and in particular, for the production of various mortar mixtures. The apparatus includes metering means, control means and transfer means for metering out and introducing predetermined quantities of components into a mixer and thereupon, after mixing, delivering the mixed product into means for loading transportation vehicles. The apparatus has no intermediate containers for storing various mixtures of building materials. A mixer is provided which can be emptied residue-free. A self-cleaning conveying system from the mixer to each transfer device is further provided. The lower wall zone of the mixer can be completely opened for residue-free emptying, the opening angle being greater than the angle of slide of the mixing material or residues thereof in the mixer. Such an opening prevents appreciable residues from being left in the mixer and from contaminating subsequent mixtures.

Abstract: A mixing tower for concrete or the like has a series of superimposed prefabricated modules which are connected to one another and include a cylindrical lowermost module, a frustoconical intermediate module with several outlets which is integral with the top of the lowermost module, and several larger-diameter cylindrical modules above the intermediate module. The modules contain prefabricated mixers, controls, scales and/or analogous aggregates which are assembled with the respective modules at the manufacturing plant and are coupled to each other at the locus of erection of the tower, preferably by coupling devices each of which is disposed at the level of connection between the respective modules.

Abstract: Moist pourable material which is required to be in dry condition, is dried by heating and drying a portion of the material and then mixing this portion with the remaining moist portion, so that the heat of the heated dry portion will heat and dry the remaining portion. A method and an apparatus are disclosed.

Abstract: Apparatus for mixing metered quantities of cement with metered quantities of water has a horizontal housing with a first section having an inlet for admission of cement, a cylindrical intermediate section which receives cement from the first section, and a mixing chamber which receives cement from the intermediate section and further receives metered quantities of water by way of a pipe. A feed screw is rotatably mounted in the first and intermediate sections to convey cement toward and into the mixing chamber. The thread of the feed screw carries radially outwardly extending paddles which are located in the first section and prevent accumulations of cement in the space around the corresponding portion of the feed screw. The mixing chamber is connected to the intermediate section by a hinge and contains a rotary mixing element whose shaft is separably coupled to the core of the feed screw.

Abstract: Apparatus for the preparation of mortar has a wheel-mounted frame for an elongated vessel which receives metered quantities of solid and liquid constituents from discrete feeding units. The vessel has an outlet and contains a rotary homogenizing and evacuating device which mixes the solid and liquid constituents to form mortar and advances the mortar toward and through the outlet. Mortar issuing from the outlet of the vessel can be discharged into a separate container which is mounted in or on the frame and is connected with one or more evacuating pumps, into wheelbarrows or into the container of a conventional mortar mixing machine. The feeding unit for solid constituent may receive material by gravity flow or under the action of a rotary screw in a receptacle which is mounted in the frame at a level above the vessel and receives solid constituent from a pneumatic conveyor.